BMC Geriatrics The feasibility of measuring the activation of the trunk muscles in healthy older adults during trunk stability exercises

Edwin Y Hanada
Department of Medicine
Capital District Health Authority and Dalhousie University
HalifaxCanada

Cheryl L Hubley-Kozey email@example.com
†2
School of Physiotherapy
Dalhousie University
HalifaxCanada

School of Biomedical Engineering
Dalhousie University
HalifaxCanada

Melissa D Mckeon firstname.lastname@example.com
School of Physiotherapy
Dalhousie University
HalifaxCanada

Sarah A Gordon email@example.com*correspondingauthor†equalcontributors
School of Physiotherapy
Dalhousie University
HalifaxCanada

BMC Geriatrics The feasibility of measuring the activation of the trunk muscles in healthy older adults during trunk stability exercises
10.1186/1471-2318-8-33BioMed Central Page 1 of 13 (page number not for citation purposes) Research article
Background: As the older adult population increases, the potential functional and clinical burden of trunk muscle dysfunction may be significant. An evaluation of risk factors including the impact of the trunk muscles in terms of their temporal firing patterns, amplitudes of activation, and contribution to spinal stability is required. Therefore, the specific purpose of this study was to assess the feasibility of measuring the activation of trunk muscles in healthy older adults during specific leg exercises with trunk stabilization.Methods: 12 asymptomatic adults 65 to 75 years of age were included in the study. Participants performed a series of trunk stability exercises, while bilateral activation of abdominal and back extensor muscles was recorded by 24 pairs of Meditrace™ surface electrodes. Maximal voluntary isometric contractions (MVIC) were performed for electromyographic (EMG) normalization purposes. EMG waveforms were generated and amplitude measures as a percentage of MVIC were calculated along with ensemble average profiles. 3D kinematics data were also recorded, using an electromagnetic sensor placed at the left lateral iliac crest. Furthermore, a qualitative assessment was conducted to establish the participant's ability to complete all experimental tasks.Results: Excellent quality abdominal muscle activation data were recorded during the tasks. Participants performed the trunk stability exercises with an unsteady, intermittent motion, but were able to keep pelvic motion to less than 10°. The EMG amplitudes showed that during these exercises, on average, the older adults recruited their abdominal muscles from 15-34% of MVIC and back extensors to less than 10% of MVIC. There were similarities among the abdominal muscle profiles. No participants reported pain during the testing session, although 3 (25%) of the participants reported delayed onset muscle soreness during follow up that was not functionally limiting.Conclusion:Older adults were able to successfully complete the trunk stability protocol that was developed for younger adults with some minor modifications. The collected EMG amplitudes were higher than those reported in the literature for young healthy adults. The temporal waveforms for the abdominal muscles showed a degree of synchrony among muscles, except for the early activation from the internal oblique prior to lifting the leg off the table.

Background

Biomechanical research has demonstrated the role of trunk muscle activation during functional activities and exercise [1]. The significance of the trunk muscles for spinal stability has been previously established in workingage adults, and has been linked to prevention and rehabilitation of low back pain (LBP) [2]. In particular, endurance and coordination of trunk muscle activity are key characteristics to maintain the stability of the spine, and therefore decrease the effects of low back pain [1]. Furthermore, it has been demonstrated that trunk muscle activity occurs during locomotion, and while the precise role is not well understood, the evidence suggests that the trunk muscles fulfill a critical role in the dynamic control of posture [3]. A link between trunk muscle function, low back pain, and physical function in older adults has been reported [4]. It is clear that both the abdominal and the back extensor muscles are key components that contribute to spinal stability [1] and functional stability [3]. Given these interrelationships and the desire to prevent falls in this group, there is a need for better assessments of trunk muscle activation in older adults.

LBP is one of the most common medical disorders in older persons, affecting up to half of those over 65 years of age [5]. In the Iowa 65+ Rural health study, LBP was reported by 23.6% of older women, and by 18.4% of older men in the year prior to the survey [6]. There is an enormous health care cost for LBP in older adults, as nearly 75% of persons with this disorder may utilize medical and chiropractic services, while 25% have at least one hospitalization directly related to LBP, and 5% of participants have low back surgery [6]. Furthermore, 15 to 40% of the elderly respondents reported some type of disability, in the form of limitation in walking, sitting, bending over, and performing household chores, while 21% of the participants attributed sleep disturbance to the LBP [6].

In older adults, trunk extensor strength declines more quickly with aging than does appendicular strength [7]. This loss of strength in axial muscles has been associated with kyphosis [8]. Research has revealed that older adults have a delayed response in the onset of trunk muscle activation, a reduction in amplitude in paraspinal muscle firing, and smaller stretch reflexes in response to dynamic stability perturbations [9]. Furthermore, in a cross-sectional analysis of older adults, through multivariate models, isometric trunk extensor strength was demonstrated to be predictive of maximal walking speed among women, but not men [10]. A more recent study demonstrated that higher fat infiltration around the spine in persons aged 70 to 79 years was associated with reduced functional capacity as reflected by compromised balance [4]. Finally, Hwang et al. (2008) has confirmed that feed-forward responses of the paraspinal muscles are compromised in older adults based on response times reported for expected and unexpected perturbations.

With the older adult population (65+ years) being a fast growing age group in North America, we should expect to see the incidence of LBP and functional decline increase. An evidence-based approach to treatment is required to help mitigate the potential for spiraling health care costs and increased disability. The potential functional and clinical burdens of trunk muscle dysfunction in this population will be significant. Therefore, further evaluation of risk factors is required, including the impact of the trunk muscles with respect to their temporal firing patterns, amplitude of activation, and their contribution to spinal stability. Methods for measuring trunk muscle function have previously been established for younger adults [11,12], but very little is known about these methods in the older adult population. This study will focus on a legloading exercise that requires the abdominal muscles to respond to minimize lumbo-pelvic motion [11,13,14].

The long term goal is to improve diagnostic assessment tools for the "trunk" stabilizing muscles, and to better understand how impairments such as LBP affect the neuromuscular responses, so that we may improve our understanding of therapeutic exercises used in the management of LBP, especially in the older population. The specific objectives of this study were i) to assess the feasibility for measuring the activation of the trunk muscles in an older adult population, ii) to determine the safety of a method for measuring co-activation of trunk muscles, and iii) to quantify trunk muscle activation patterns during a legloading task that has been used as both an assessment tool and a therapeutic exercise.

The original protocol was used to investigate neuromuscular patterns of working-age adults (20-50 yrs) during a dynamic exercise stability test [11] that was designed to challenge spinal stability. Previous work has illustrated that those with LBP respond to the demands of dynamic challenges differently than those without LBP [13,[15][16][17][18]. Although there may be serious consequences of neuromuscular impairments of the trunk muscles, including its effects on LBP and mobility in older adults, the authors are not aware of any published study that focuses on the characterization of trunk muscle activation of older adults during a therapeutic exercise.

Methods

Participants

Sixteen asymptomatic healthy adults between 65 to 80 years of age were recruited through word of mouth to participate in the study. Participants were excluded if they had a history of LBP, previous abdominal or back surgery, previous spinal fracture, or any other major musculoskel-etal, cardio-respiratory, or neurological condition. Throughout the screening process, 4 individuals (2 males, 2 females) were excluded due to medical problems (arrhythmia, coronary artery disease, osteoporosis), leaving 12 individuals (7 males, 5 females) to participate in the study.

Screening & Questionnaires

Prior to participation, all individuals were required to read and sign an informed consent approved by the Capital Health District's Research Ethics Board. All participants were interviewed to determine any medical conditions that would prevent their participation in the study, their health status, and information regarding participation in regular abdominal exercise and fitness routines.

Participants were asked to attend two testing sessions: the first one being 30 minutes in duration, and the second session 2 hours. During the first session, a postural and neurological assessment was conducted by a physiotherapist to screen for any obvious fixed abnormal spinal postures (kyphosis, lordosis, or scoliosis) and lower extremity neuromuscular deficits (myotomal strength, reflexes, and dermatomal sensation). Furthermore, a mental status examination was performed to ensure adequate cognitive ability to participate in the research study (score > 23) [19]. Standard demographic data was collected from each individual, including age, sex, occupation, and anthropometric data such as mass (in kilograms), height (in centimeters), and waist circumference (in centimeters). Body mass index (BMI) was calculated from the height and mass measures. Demographic data is found in Table 1.

Trunk Stability Exercise Protocol

Three levels of a trunk stability exercise protocol [11,16] were used to progressively challenge the individual's stabilizing system without placing high mechanical loads on the lumbar vertebrae. During the first testing session, participants were shown and given a verbal description of each exercise and told to practice each of the 3 levels 5 times on 3 separate occasions before returning for their second testing session.

During the second testing session the trunk stability exercises were performed in random order to minimize effects of fatigue and learning. Each exercise was repeated three times with a one-minute rest between trials. The start and end position for each exercise level was standardized, with participants lying in a supine position and knees flexed to 90°. Participants were given instructions to activate the abdominal muscles prior to lifting or extending their legs.

In Level I of the exercise, participants were instructed to lift their right foot off of the table and flex the knee and the hip to 90° and have the thighs contact the wooden frame, then lift the left foot off to the same position, then lower the legs (left then right) to return to the starting position. Level 2 of the exercise protocol added a right knee extension phase after the left thigh came in contact with the wooden frame, as shown in Figure 1. The right heel slid along the table until the knee was fully extended, upon which the hip and knee were then flexed and returned to the 90° hip angle position, and subsequently both legs were lowered to the starting position (left then right). Level 3 repeated the sequence of level 2, except that the foot did not touch the bed until the knee was fully extended [11]. At full extension, only the heel was briefly tapped on the bed before the right leg was returned to the wooden frame without further contact with the bed.

Electronic switches were placed on the right thigh and the plantar surface of the right foot to identify temporal events so that the motion could be subdivided into distinct phases of lift, extend, and lower. The total exercise was defined from right foot off the bed to right foot back on the bed. For levels 2 and 3 the extension phase was from knee off the wooden frame to knee back on the wooden frame

Normalization Exercises

Normalization exercises followed the trunk stability exercises to elicit the maximal voluntary isometric contraction (MVIC). Participants performed a randomized series of isometric exercises in an attempt to recruit all motor units for amplitude normalization purposes. Exercises for each muscle site were chosen based on previous work [20][21][22] and muscle functional testing procedures [23]. While other methods of normalization have been used to answer specific questions [24], normalizing to MVIC is an acceptable standard for comparison but the results need to be interpreted within the limitations of this procedure [25]. The idea of using a variety of exercises is important to elicit maximal contractions from the abdominal muscles [21,26] and providing feedback and motivation to the participant are necessary to increase the potential for elic- iting a maximum effort [27]. The exercises included a resisted sit-up, back extension, lateral bend and trunk rotation and all have been used in previous studies on asymptomatic controls and those with low back pain [11,13,16]. In all exercises, the participants were stabilized using Velcro straps and applied manual resistance to minimize potential movement. Each exercise was repeated twice with a two-minute rest between exercises to minimize fatigue.

Electromyography (EMG)

Surface EMG (3-AMT-8, Bortec™, Canada) was recorded from 24 muscle sites on the abdomen (12) and back (12) while participants performed the trunk stability exercise tasks. The electrode placements were selected to provide information on bilateral sites for a comprehensive set of abdominal and back extensor muscle sites [28] and the sites are consistent with de Seze's recent work [29]. Medi-trace™ Ag/Ag Cl surface electrodes (10 mm diameter, bipolar configuration 30 mm centre-to-centre) were attached after standard skin preparation to the left and right sides of the: i) lower rectus abdominis (LRA): centered on the muscle belly midway between the umbilicus & the pubis [30]; ii) upper rectus abdominis (URA): centered on the muscle belly midway between the sternum & the umbilicus [30]; iii) external oblique anterior fibres (EO1): over the 8 th rib adjacent to the costal cartilage [31]; iv) external oblique lateral fibres (EO2): 15 cm lateral to the umbilicus oriented at 45° [21]; v) external oblique posterior fibres (EO3): midpoint between the lowest part of the ribcage and the iliac crest and vi) internal oblique (IO): centered in the triangle formed by the inguinal ligament and lateral border of the rectus abdominis sheath and the line between the anterior superior iliac spine [32]. For the back extensors, electrodes were attached at. four sites on the erector spinae: vii and viii) lumbar longissimus 3 cm from the spinous process at lumbar level 1 (L1-3) and level 3 (L3-3) [33][34][35]; ix) and x) lumbar ilio-Level 2 of the exercise progression as per the description in the text Figure 1 Level 2 of the exercise progression as per the description in the text. The heel slides along the table until the right knee is fully extended. Electronic switches are located on the right foot [B] which contacts with the metal plate located on the table [A] and the right thigh [C] which contacts with the wooden frame [D] to identify temporal events so that the motion may be divided into distinct phases. The total exercise was from foot off the bed to foot back on the bed. For levels 2 and 3, the knee extension phase was from knee off the wooden frame to knee back on the wooden frame.

costalis 6 cm from the spinous process at lumbar level 1 (L1-6) and level 3 (L3-6) [33][34][35]; xi) multifidus 2 cm from spinous process at lumbar level 5 (L5-2) [22]; and xii) a site over the quadratus lumborum 8 cm from the spinous process at lumbar level 4 (L4-8) [36,28] that was verified in pilot work on cadavers for a total of 24 recording sites. These placements were used as a general guide and minor adjustments were made for different body sizes.

There were some difficulties in locating landmarks for EMG electrode placement and electrode adherence due to skin movement. The electrodes were placed during standing and then verified using palpation and resisted exercises to ensure proper placement and to assess cross talk while participants were in the supine position. The exercises for verification attempted to isolate the specific muscle site and were based on manual muscle testing [23,37]. The back extensor sites were stable between the standing and lying position. However, minor adjustments were made for a small number of subjects in which movement due to adipose tissue occurred between standing and lying supine for some abdominal sites. The normalization exercises were used as a validation for proper placement, since exercises were aimed at recruiting specific abdominal muscles and minimizing activity in other muscles.

Motion Capture

A Flock of Birds Motion Capture™ system was used to record the angular motion of the pelvis during the tasks. A sensor was placed on the antero-superior portion of the left lateral iliac crest. The sensors detected changes in 3 D motions with respect to a global reference providing an overall measure of motion, but the measurements can not be related directly to an anatomical reference ( Figure 2). The motion data was synchronized to the EMG data via the external sensors with each motion profile normalized to 100% time. The motion data was used to ensure minimal movement of the trunk and pelvis and to confirm that participants were able to maintain their lumbar pelvic position of a neutral spine throughout all tasks.

Data processing and analysis

Root mean square amplitudes were calculated for the total exercise for all three levels and for the extension phase for levels 2 and 3. These amplitudes were normalized to the % MVIC [11,38]. In addition, the raw EMG signals were full-wave rectified and low pass filtered at 6 Hz using a second order recursive Butterworth filter to yield a linear envelope waveform. The waveforms were time normalized for the total exercise and then amplitude normalized to the %MVIC. Ensemble average waveforms were calculated for each muscle and a coefficient of variation for the waveforms [39].

The maximum difference in angular motion around the three axes was calculated during the entire exercise for all three levels and for the leg extension phase of levels 2 and 3.

Results

Participants

Participants were recruited from the local community and had several years of university/college education (oceanographer (2), teacher/professor (3), social worker (2), supervisor, superintendent, engineer, librarian, and physician). Four older adults were excluded after the first session due to health problems pertaining to the health screening questionnaire, as previously detailed in the methods section. All 12 participants (7 men and 5 women) participated in both testing sessions, leaving a 0% drop-out rate.

Trunk Stability Exercise

Throughout the first session, the older adults were found to have difficulty following and remembering instructions. This problem was resolved by simply demonstrating the actions, in addition to verbalizing the instructions. It was found that the older adults performed the exercises with intermittent, jerky motions as opposed to a smooth motion. An attempt was made to correct this throughout the first session and participants were instructed to practice these smoothed movements at home. Subsequently, performance was improved from a qualitative perspective during the second session.

Normalization and Validation Exercises

Three participants (25%) were instructed to perform the normalization exercises at a sub-maximal effort given their history of hypertension. Furthermore, it was necessary to remind the participants to breathe throughout the trunk muscle contractions, due to the possibly harmful increase in intra-thoracic/intra-abdominal pressure associated with the Valsalva maneuver. The male participants reported "not being able to push as hard if they did not hold their breath". In contrast, it is uncertain whether the women exerted a true maximum effort based on selfreport and the observed absence of visible exertion. During normalization trials the men were not hesitant to express fatigue and the need to rest between trials, but the women often reported "feeling fine" and being "ready to go again" immediately following each trial. However, in order to minimize the effects of fatigue, the standard rest time (120 sec) was applied for both groups.

Motion

Participants were able to minimize pelvic motion during the total exercise to an average less than 10° and to less than 5° during the extension phase of the trunk stability tasks for all three axes as shown in Table 2. Figure 2 Motion capture. The Flock of Birds Motion Capture™ sensor was placed on the antero-superior portion of the left lateral iliac crest. Note that the z-axis is positioned perpendicular to the sensor. This sensor records motion with respect to a fixed global reference and not an anatomical reference.

Motion capture

Electromyography

Although there were some challenges to the fixation of the electrodes to the participants' skin that included: 1) difficulty in locating landmarks for EMG electrode placement because of loose skin and excess adipose tissue, and 2) electrode adherence to the skin during movement, all EMG signals were of high quality, with excellent signal to noise ratios. Examples of the abdominal signals are illustrated in Figure 3. There was low amplitude noise from the magnetic motion sensors, but this had no affect on the Means (SD) are displayed for Yaw (motion about the Z-axis), Pitch (motion about the y-axis), Roll (motion about the x-axis) with respect to a global reference. abdominal muscles and had no visible effect on the back extensor muscles. Pilot work showed that the low level noise decreased the further the sensor was from the transmitter, and that it was negligible when at a distance greater than 60 cm. For the exercise tasks, this distance was greater than 60 cm. The mean amplitude for all 24 muscle sites is presented in Table 3. As expected, participants activated back extensor muscles to low amplitudes, with all sites less than 10% MVIC. The abdominal muscles were recruited to amplitudes from 15% to 35% MVIC (lower amplitudes for level 1, higher amplitudes for level 3). The ensemble average profiles are in Figure 4 for levels 1-3. The coefficients of variation for these waveforms are found in Table 4. These profiles illustrate how the muscles respond to the changes in loading throughout the trunk stability tasks. Of note is the higher bilateral internal oblique amplitude initially for all exercise levels.

Pain

No participants reported pain during the testing, and all participants were able to complete the full protocol with some minor adjustments to the normalization exercises as previously discussed. Follow-up phone calls were made to all participants following the testing sessions. Three men reported mild delayed-onset muscle soreness, although they were not limited in their daily function.

Discussion

Generally, older participants were able to perform the exercises necessary for surface EMG measurement of trunk muscle activation patterns without significant difficulty, much like their younger cohorts demonstrated in previous studies [11,16]. Most importantly, they were able to perform the normalization procedures and exercise tasks safely, and without any major adverse health sequelae. For the former, however, three participants were instructed not to perform maximal level exercises because of their hypertension. All three were males and their percent MVIC values were not the highest for the test exercise. It was assumed that they produced an effort that was within normal variability for maximum efforts. Discussion of the implications of this alteration in procedure is discussed below. The results have important positive implications for future studies that focus on the activation of trunk muscles by demonstrating the feasibility of collecting comprehensive electromyographic data during this standardized task in healthy older adults.

Modifications were made to the protocol for older persons, both to increase the margin of safety and to enhance the probability of success in performing the tasks. For example, during the normalization procedure, participants were constantly reminded to breathe throughout the isometric contractions in order to reduce the potential effect of exercise-induced high blood pressure from a continued Valsalva maneuver, as found in a previous study [40]. Although there were minor challenges in participants learning to perform the trunk stability exercises, the addition of a live demonstration of these tasks to the participants helped to overcome any major obstacles to older adults being able to successfully perform these tasks. Adipose tissue in the older adult participants made it challenging for the investigators to properly palpate musculoskeletal landmarks, and ensure that the electrodes were secure. Shifting of the electrodes occurred during the tasks, and some of the electrodes were required to be readjusted. However, this could happen in younger participants with increased waist circumference, and is not a challenge strictly for the older cohorts. Nevertheless, despite the challenges in the older adults, the validation exercises confirmed that the electrodes were properly placed and quality electromyography signals were recorded from the trunk muscles.

Excellent quality data was successfully recorded in the older adults during the leg-loading exercises. It was important that the older adults performed the exercise correctly and the motion data supports that they were able to minimize pelvic motion during performance of the exercise. The recorded motions gave an overall assessment of the pelvic motion with respect to a global reference and all angular displacement differences were less than 10 degrees. The older adults did not produce high levels of activity in the back extensor sites (< 10% MVIC) during performance of the exercise although they were higher than reports for younger adults [11,16]. The results also showed a degree of symmetry between the left and the right abdominal muscle sites, although a few (3/12) abdominal muscles had greater than a 4% MVIC difference between sides for the single-leg extension exercises i.e. EO1 for level 2 and 3 and EO3 for level 2. The increase in amplitude of activation from level 1-3 is consistent with reports for younger adults. However, the abdominal muscle amplitudes were slightly higher than amplitudes reported for younger adults [11,16]. This may reflect the decrease in strength for an older adult [41] and subsequently their need to work at a higher percentage of MVIC to perform the same task. As previously mentioned, three participants did not perform maximal exercises for normalization purposes due to their heart conditions. This could also explain the slightly higher amplitude for the older adults compared to the literature for young adults [11,16]. While it is recognized that there are limitations in using maximum voluntary activations for normalization purposes, and others have explored different normalization procedures [24,42], the results do provide an indication of the amplitude of muscle activity during the exercise compared to their voluntary maximum and allows for comparisons among muscles [43]. There will be variability in how forceful individuals voluntarily contract their muscles, and on average it has been shown to be 94% of the maximum amplitude produced during a burst superposition for the knee extensors [27]. In the present case, the average difference between including those that did sub-maximum and not including them was 0.76% MVIC. The results show that for all exercise levels, the activation did not exceed 35% of MVIC, so at best these exercises produced moderately low activation amplitudes in this group. It was also noted that in studies that use MVICs for normalization purposes, that comparison among studies show consistency in amplitudes and allows for conclusions to be drawn with respect to the demand that an exercise has on recruiting specific muscles [44]. Therefore the implication of sub maximal efforts is that the amplitudes as a percentage of maximum for the test exercises were overestimated and the exercises elicited even lower percent MVICs than presented in table 2.  Table 4.

Raw EMG data

Sample ensemble average waveforms

Since the amplitudes recruited for the abdominal muscles were less than 35% of MVIC, this indicated that even the highest exercise level would not suffice as a strength training protocol. This conclusion is based on the American College of Sport Medicine guidelines for exercise training in older adults [41]. However, the exercises appear to be beneficial for recruiting trunk muscles, especially the abdominal muscles that are not normally recruited in every day activities. Furthermore, the coordination of trunk muscle activity that would be encouraged by performing the exercises in this protocol are considered important for spinal stability [44]. The coefficients of variation for this older adult are similar to those reported for younger asymptomatic subjects, but lower than those reported for young adults [16] with chronic low back pain [13].

The profiles illustrate the participants activated their abdominal muscles to a relatively consistent level throughout the exercise and did not have specific responses to the different phases within the exercise (i.e. a constant co-activation among the synergists rather than a response to the different loading associated with the leg lift/lower phases and leg extension phase). While one may argue that the instructions were specific to stabilize the pelvis resulting in co-activity, an asynchronous firing pattern was previously reported for those who had low back pain who were given the same instructions [15]. The higher level of activation of the internal oblique prior to the second leg lifting from the table suggests that it has an important role initially for stability, whereas the other muscles respond to the leg lifting portion of the exercise. This pattern for the internal oblique may have been a result of the instructions to stabilize the pelvis prior to lifting the foot off of the table.

There were several limitations regarding the generalizability of this study. Firstly, all of the participants were well-educated and therefore they may have been able to perform this task with a lesser degree of difficulty than an older adult who was not as well educated. This may be especially true, since some of the participants may have been more likely to engage in procedural, executive tasks in their daily work environment. Secondly, only 3 of the participants were over 70 years of age, and the extent that "older old" adults, such as those persons who were over 80 years of age, could perform the tasks was not determined in this study, and should be explored in future studies. Finally, these volunteers were healthy, and the degree to which older adults with back pain or mobility impairments could or would participate has not been determined. However, it is the authors' opinion that the protocol that was utilized could be sufficiently modified to accommodate for individuals with various impairments.

Another concern with the current protocol may be with the normalization procedure using maximal contractions. Kasman [43] acknowledged that while the participant with pathology may not be able to activate their muscles to a maximum amplitude, that it is still important to report the percentage of their maximal voluntary amplitude at which they are willing to recruit. Previous research demonstrated that even participants with joint pathology and pain are able to voluntarily activate their muscles to over 94% of their maximum when provided with learning and feedback [27]. While Lewek's study [27] was performed on lower limb muscles and not trunk muscles, it should be noted that these exercises have been used as a method for normalization for those with chronic low back pain with no adverse effects [13]. Given the lack of gold standard for EMG normalization, while it has its limitations and must be interpreted within these limitations, the MVIC is still the best standard for comparison among muscles [25,45].

Further research will be required to determine whether the protocol can be safely applied to an older adult population with various musculoskeletal disorders, such as LBP, again paralleling the research conducted on younger adults. A comparison study on younger sex-matched adults will help to elucidate the nature of the differences.

Conclusion

Older adults were able to successfully complete the trunk stability exercise protocol to measure trunk muscle activation that was previously used for younger adults, with some minor modifications to the protocol with respect to instructions and normalization exercises. There were no adverse effects reported during or following the procedure. Quality EMG data from 12 bilateral trunk muscle sites were recorded during performance of the exercise allowing for study of co-activation among muscles during specific phases of the protocol. The older adults used low to moderate activation amplitudes to perform the trunk stability exercises. These results provide a foundation for future studies to evaluate the utility of EMG recordings of the trunk muscles during a limb-loading task as a clinical assessment tool for older adults with pathology. The paper established that this protocol for evaluating trunk muscle function was feasible, and that quality EMG records were obtained from this older adult group.

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Figure 3
3Raw EMG data. Examples of the raw EMG signals from the lower rectus abdominus [LRA], and external oblique [EO3] during level 3 of the exercise progression. This provides an indication of the quality of the data.

Figure 4
4Sample ensemble average waveforms. Sample ensemble average waveforms normalized to %MVIC for the 6 abdominal muscles during 3 levels of the exercise progression. [A] Level 1 [B] Level 2 [C] Level 3. Note that three participants did not produce maximal activations during normalization exercises. Coefficients of variation are in

Table 1 :
1Subject demographic data displayed as means and standard deviations for age, mass, height, BMI, and waist girth.Age
(yrs)

Mass
(Kg)

Height
(cm)

BMI
(Kg/m 2 )

Waist girth
(cm)

Group
68.7 (± 3.5)
79.1 (± 14.8)
170.0 (± 9.3)
27.2 (± 3.5)
91.2 (± 13.2)

Table 2 :
2Maximum motion (in degrees) about the sensor for the total exercise for all 3 exercise levels and for the leg-extension phase of levels 2 and 3.Total
Leg-extension
Yaw
Pitch
Roll
Yaw
Pitch
Roll

Level 1
5.7 (± 3.4)
4.7 (± 2.2)
6.8 (± 3.7)
--
--
--
Level 2
7.0 (± 3.5)
7.5 (± 3.8)
9.5 (± 5.1)
3.1 (± 1.9)
4.0 (± 2.7)
4.3 (± 3.3)
Level 3
6.8 (± 2.9)
7.3 (± 3.6)
8.9 (± 4.6)
2.8 (± 1.2)
3.6 (± 2.5)
3.3 (± 2.6)

Table 3 :
3Mean (SD) RMS amplitudes normalized to a maximal effort contraction (%MVIC) for the total exercise for level 1 and for the leg extension phase of levels 2 and 3.Abdominal Muscles
Back Extensor Muscles
Right
Left
Right
Left

Level 1
Total Exercise

LRA
15.6
(± 6.6)

15.6
(± 5.4)

L1-3
6.1
(± 2.2)

5.7
(± 1.8)
URA
16.4
(± 10.3)

14.5
(± 6.5)

L1-6
8.1
(± 2.5)

8.1
(± 2.7)
EO1
22.5
(± 13.4)

21.6
(± 6.8)

L3-3
5.2
(± 1.2)

4.6
(± 1.4)
EO2
20.7
(± 10.5)

20.0
(± 12.9)

L3-6
5.4
(± 2.1)

5.3
(± 1.7)
EO3
24.9
(± 9.1)

21.5
(± 9.2)

L4-8
8.2
(± 2.3)

7.5
(± 3.7)
IO
22.4
(± 14.1)

22.4
(± 9.4)

L5-2
7.2
(± 2.7)

7.1
(± 2.6)

Level 2
Leg Extend

LRA
18.4
(± 7.4)

17.2
(± 5.2)

L1-3
5.2
(± 1.9)

5.3
(± 1.6)
URA
17.4
(± 8. 6)

16.5
(± 7.2)

L1-6
6.6
(± 1.8)

8.1
(± 3.2)
EO1
25.0
(± 10.5)

21.0
(± 9.1)

L3-3
4.9
(± 1.8)

5.2
(± 2.7)
EO2
22.7
(± 10.6)

19.8
(± 10.9)

L3-6
4.9
(± 2.4)

6. 6
(± 3.2)
EO3
27.6
(± 8.5)

22.9
(± 9.2)

L4-8
7.0
(± 2.3)

8.8
(± 4.1)
IO
23.4
(± 13.7)

20.6
(± 6.6)

L5-2
7.0
(± 3.0)

7.2
(± 2.7)

Level 3
Leg Extend

LRA
25.4
(± 12.5)

23.2
(± 9.5)

L1-3
5.5
(± 2.4)

5.5
(± 2.1)
URA
24.9
(± 14.4)

23.4
(± 13.2)

L1-6
7.0
(± 2.0)

8.6
(± 3.9)
EO1
33.3
(± 13.0)

28.5
(± 15.2)

L3-3
5.1
(± 2.0)

5.4
(± 3.1)
EO2
27.3
(± 11.1)

26.8
(± 19.9)

L3-6
5.0
(± 2.1)

7.0
(± 3.6)
EO3
33.8
(± 9.9)

30.4
(± 17.9)

L4-8
7.5
(± 2.9)

9.5
(± 4.5)
IO
27.3
(± 13.8)

23.9
(± 9.2)

L5-2
7.1
(± 3.4)

7.4
(± 3.1)

Table 4 :
4Coefficients of variation for ensemble average waveforms for levels, levels 1-3 of the trunk stability exercise task.Abdominal Muscles
Back Extensor Muscles
Right
Left
Right
Left

Level 1
LRA
0.50
0.41
L1-3
0.43
0.40
URA
0.67
0.53
L1-6
0.39
0.45
EO1
0.72
0.42
L3-3
0.33
0.37
EO2
0.57
0.61
L3-6
0.42
0.37
EO3
0.48
0.47
L4-8
0.33
0.52
IO
0.68
0.49
L5-2
0.45
0.41

Level 2
LRA
0.49
0.40
L1-3
0.39
0.36
URA
0.59
0.53
L1-6
0.33
0.44
EO1
0.60
0.49
L3-3
0.38
0.48
EO2
0.56
0.59
L3-6
0.48
0.47
EO3
0.43
0.44
L4-8
0.35
0.51
IO
0.68
0.46
L5-2
0.45
0.39

Level 3
LRA
0.56
0.48
L1-3
0.45
0.42
URA
0.61
0.60
L1-6
0.38
0.50
EO1
0.51
0.52
L3-3
0.38
0.52
EO2
0.50
0.69
L3-6
0.44
0.47
EO3
0.39
0.55
L4-8
0.39
0.52
IO
0.59
0.44
L5-2
0.48
0.44

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AcknowledgementsThe authors wish to acknowledge the Nova Scotia Health Research Foundation for providing necessary funding, Marilynn Abbott for her valuable assistance in this project, and the participants who donated their time and effort to the successful completion of this project.Competing interestsThe authors declare that they have no competing interests.ConsentA copy of the written consent is available for review by the Editor-in-Chief of this journal.Authors' contributionsEH: Designed study, manuscript preparation/editing and interpretation. CHK: Designed study, manuscript preparation/editing, analysis and interpretation. MM: Manuscript preparation, data analysis. SG: Recruited and collected data, manuscript editing.Pre-publication historyThe pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2318/8/33/prepub
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BMC Public Health The prevalence of self-reported deliberate self harm in Irish adolescents

Carolyn Morey email@example.com
National Suicide Research Foundation
1 Perrott Avenue, College RoadCorkIreland

Inspire Foundation
Rozelle NSW 2039PO Box 1790Australia

Paul Corcoran
National Suicide Research Foundation
1 Perrott Avenue, College RoadCorkIreland

Ella Arensman
National Suicide Research Foundation
1 Perrott Avenue, College RoadCorkIreland

Ivan J Perry
Department of Epidemiology and Public Health
University College Cork
Room 2.51

Brookfield Health Sciences Complex
College RoadCorkIreland

BMC Public Health The prevalence of self-reported deliberate self harm in Irish adolescents
10.1186/1471-2458-8-79BioMed Central Page 1 of 7 (page number not for citation purposes) Research article
Background: Deliberate self harm is major public health problem, in particular among young people. Although several studies have addressed the prevalence of deliberate self harm among young people in the community, little is known about the extent to which deliberate self harm comes to the attention of medical services, the self harm methods used and the underlying motives. The aim of this study was to determine the prevalence of deliberate self harm in adolescents and the methods, motives and help seeking behaviour associated with this behaviour.Methods:A cross-sectional survey using an anonymous self-report questionnaire was administered in 39 schools in the Southern area of the Health Service Executive, Ireland. Of the 4,583 adolescents aged 15-17 years who were invited to participate in the survey, 3,881 adolescents took part (response: 85%).Results:A lifetime history of DSH was reported by 9.1% (n = 333) of the adolescents. DSH was more common among females (13.9%) than males (4.3%). Self cutting (66.0%) and overdose (35.2%) were the most common DSH methods. A minority of participants accessed medical services after engaging in DSH (15.3%).Conclusion: DSH is a significant problem in Irish adolescents and the vast majority do not come to the attention of health services. Innovative solutions for prevention and intervention are required to tackle DSH in adolescents.

Background

Deliberate self harm (DSH) is a major public health problem in Ireland. Young people are those most at risk, particularly young women aged 15-19 years who had the highest incidence of DSH based on hospital presentations to A&E departments in 2004, 606 per 100,000 [1]. While the rate for young men of the same age is considerably lower, it is also notable at 301 per 100,000 [1]. These incidence rates are likely to be the 'tip of the iceberg' as they do not include cases who do not present to hospital after an act of DSH. Deliberate self harm is used to describe different types of behaviours associated with varying levels of suicide intent and a variety of motives.

The self reported lifetime prevalence of DSH found by general population studies of adolescents ranges from 2-8% [2][3][4]. Two Irish school-based studies have reported a lifetime prevalence of DSH in adolescents. In a sample of 88 [13][14] year-olds a lifetime prevalence of self harm of 2-3% was reported [5], while Lynch and colleagues found a lifetime prevalence of deliberate self harm of 1.5% among adolescents aged 12-15 years [6]. In two studies, the self reported life time prevalence of self harm thougths was reported, which was 44% [5] and 45.7% [7]. This paper reports the findings of a large-scale schoolbased survey in Ireland that investigated the prevalence of DSH and self harm thoughts in [15][16][17] year olds. Details of the methods of DSH, motives for DSH and help seeking behaviour are addressed as well.

Methods

Design and sample

A cross-sectional survey of 3,881 adolescents aged 15-17 years was carried out in 39 schools in the Health Service Executive (HSE) Southern area between January 2003 and March 2004. Power calculations indicated that a minimum of 3,000 students were required to return a 95% confidence interval of 9.0-11.0% for a postulated prevalence of 10% as reported by Hawton and colleagues [8]. A list of all schools within the Southern area of the Health Service Executive was obtained from the Department of Education and schools were then divided according to whether they were in Counties Cork or Kerry or Cork city. They were further categorised as being co-educational, all male or all female. Using a random selection, 54 schools were invited to take part and 39 schools participated in the survey. Of the 4,583 students who were invited to take part, 3,881 participated in the survey, which is a response rate of 85%. Fifty one questionnaires (1.3%) were excluded from data analysis as they did not fit the age criteria (n = 25) or were not filled in seriously (n = 26).

The response rate varied by school. For 7 of the 39 schools, the response rate was lower than 75% whereas 8 schools had a response rate of at least 95%. However, there was no strong association between type of school and response rate. Non-participation was primarily because of absenteeism. In total, 90.7% of the nonresponding children were absent. Those absent due to illness or deliberately not coming to school would have a health and social profile that would be associated with a higher prevalence of DSH to those in school. However, students were also absent from school because of out-ofschool activities such as day trips and tours etc. This was the primary reason why some schools had a relatively poor response rate. Such students would be likely to have a similar prevalence of DSH to those in school at the time of the survey.

With regard to the participating and non-participating schools, single-sex girls' schools were slightly overrepre-sented among participating schools but no differences were found in terms of city/county location.

Procedure

Prior to the survey being completed, principals and teaching staff were informed about the procedure. An information sheet and opt out form were also sent to parents. On the day when the survey was carried out, students were also given the opportunity to opt out. The Clinical Research Ethics Committee of the Cork Teaching Hospitals granted ethical approval for this survey.

This survey was part of a European survey known as the Child and Adolescent Self Harm in Europe (CASE) study, which has been administered in 6 countries across Europe and one centre in Australia. A standardised internationally validated, anonymous questionnaire was designed by CASE collaborators and used for data collection by each of the centres.

The questionnaire was administered with a member of the research team being present and completed by students at school in the class room. An introduction explained the anonymity and confidential nature of the data along with the voluntary nature of students' participation. It was clarified to the students that they were free to choose whether to complete any or all of the questionnaire and their choice had no bearing on their school work. Completion of the questionnaire took 20-30 minutes. After participants had completed the survey there was a general discussion about the help and support available for young people in their local communities and each participant received a resource pack, which included a list of services in their local area. Time was made available immediately after the session for individuals who wished to ask further questions. There was also the option of contacting the National Suicide Research Foundation at any time if further assistance was required.

A distinctive characteristic of this study was that participants were asked to describe in their own words, the method(s) they had used to harm themselves. This description was then coded according to a standardised definition of deliberate self harm. The definition of deliberate self harm is as follows: "An act with a non-fatal outcome in which an individual deliberately did one or more of the following:

• Initiated behaviour (for example, self cutting, jumping from a height), which they intended to cause self harm.

• Ingested a substance in excess of the prescribed or generally recognisable therapeutic dose.

• Ingested a recreational or illicit drug that was an act that the person regarded as self harm.

• Ingested a non-ingestible substance or object."

This definition includes acts that are interrupted before self harm is inflicted, for example, a person removed from a bridge before jumping off or interrupted attempts of hanging, but excludes episodes of self harm by individuals who do not understand the meaning or the outcome of their act, for example due to a learning disability. The following questions were used to identify deliberate self harm: "Have you ever deliberately taken an overdose (e.g. pills or other medication) or tried to harm yourself in some other way (such as cut yourself)?" with response options:No/Yes, once/Yes, more than once. For those who confirmed having engaged in DSH, the questionnaire included further questions about the timing of the last act of DSH (less than a month ago/between a month and a year ago/more than a year ago), and participants were asked to describe details of the self harm act, for example the name of the drug taken in an overdose.

Episodes of deliberate self harm were then classified as a 'yes', 'no' or 'no information given' by three independent raters (CM, PC, EA) using the standardised criteria (Cohen's Kappa = 0.77). In cases where ratings were inconsistent, decisions were made based on majority rating. For those who indicated they had harmed themselves, the questionnaire included a series of questions relating to motives, methods and help seeking behaviour.

Self harm thoughts were examined by the following question: "Have you during the past month or the past year seriously thought about taking an overdose or trying to harm yourself but not actually done so?" with response options: No/Yes, the last time was in the past month/Yes, the last time was over a month ago, but less than a year ago. For those who reported self harm thoughts, the questionnaire included further questions related to help seeking behaviour.

Data analysis

Prevalence rates of deliberate self harm and self-harming thoughts were calculated with adjustment for missing data. For the prevalence rates, 95% binomial confidence intervals were calculated. Relative risks and their associated 95% confidence intervals were used to assess the differences in prevalence rates between groups.

Results

Demographics

Of the 3,830 questionnaires, 50.2% were females and the majority (53.1%) of students were 16 years of age ( Table  1). The gender balance of the sample and the proportion attending schools in Cork City and Counties Kerry and Cork were similar to the distribution of the adolescent population in the region. There was a difference in the age distribution as the sample was centred on 16 year-olds. This age accounted for just over half of the sample while the remainder were evenly made up of 15 and 17 yearolds. The general population of 15-17 year-olds were made up of almost equal proportions at each year of age.

Deliberate self harm

A lifetime history of self reported deliberate self harm was reported by 458 (12.2%, 95% CI: 11.2%-13.3%) of the teenagers surveyed (Table 2). Of the total population, 333 (9.1%, 95% CI: 8.2% -10.1%) students met the DSH definition. Of those who had harmed themselves, 45.9% had done so more than once. There were 807 (21.6%, 95% CI:

DSH and sociodemographic factors

Girls were three times more likely to harm themselves than boys (RR = 3.2 95 % CI: 2.5 -4.1; Table 1). There was no statistically significant variation with regard to age and similar prevalences of DSH were reported by the students of schools in Cork city and the counties of Cork and Kerry.

Living arrangement was associated with significant variation in the prevalence of DSH. Living with both parents was protective. Relative to teenagers with this living arrangement, DSH was significantly more common among those living with one parent (RR = 1.8 95 % CI: 1.4 -2.3) or one parent and a step parent/partner (RR = 2.2 95 % CI: 1.4 -3.4).

Methods of deliberate self harm

The majority of the teenagers who engaged in self harm did so by either cutting themselves (66.0%) or taking an overdose (35.2%) ( Table 3). Although there was a higher proportion of girls who reported cutting themselves or taking an overdose than boys, this was not significant. It is notable that boys used a greater variety of methods to harm themselves than girls. Of the 333 teenagers who had harmed themselves, 19.8% did so under the influence of alcohol, while 11.8% were under the influence of an ille-gal drug at the time when they harmed themselves. Boys (32.3%) were twice as likely as girls (15.4%) to have been under the influence of alcohol when they engaged in DSH (RR = 2.1, 95% CI: 1.3 -3.4) and four and half times more likely to have taken an illegal drug (28.1% V 6.1%, RR = 4.6, 95% CI: 2.2 -9.5). Of the 220 cases of self-cutting, 11.5% also involved an overdose.

Motives for deliberate self harm

The two most common motives reported by students for DSH were; "I wanted relief from a terrible situation" (78.9%) and "I wanted to die" (60.9%) (    (Table 5). Teenagers were more likely to contact health services after they had harmed themselves rather than before, likewise family members were more likely to be aware of the self harm after the event. Of those who harmed themselves, only 36 (11.3%) reported that they presented to hospital as a result of their DSH episode.

Discussion

In this broad representative sample of adolescents aged 15-17 years approximately one in ten reported a previous episode of DSH of whom 45.9% had done so more than once. The lifetime prevalence of DSH of 9.1% is higher compared to the prevalence of deliberate self harm reported in previous Irish school-based studies [5][6][7], which can be explained by the use of a broader definition of self harming behaviour in the present study. Only 11.3% of teenagers who harmed themselves attended hospital and fewer sought help from other medical services following their episode of DSH, findings which are consistent with other Irish studies [9,10]. Given this tendency for adolescents not to seek help and that most studies investigating deliberate self harm are based on hospital treated cases of deliberate self harm [11], previous estimates of the extent of deliberate self harm may have been underestimated.

The one-year prevalence rate based on the study definition criteria was 5.7%. Considering their lifetime history of DSH, 11.3% of the teenagers had attended hospital at least once. This figure reduced to 8.3% when only considering cases of DSH that occurred in the past year. Combining the one-year prevalence and its associated figure for hospital attendance indicated that the annual incidence of hospital-treated adolescent DSH in the region was 473 per 100,000. This is 54% higher than the rate of 307 per 100,000 calculated for [15][16][17] year-olds of the region based on data from the National Registry of Deliberate Self Harm [1]. Possible reasons for this discrepancy include the broader definition used in the school-based study, adolescents underestimating the time to their previous DSH, and DSH episodes going undetected within the hospital system.

Unlike many other self-report studies examining deliberate self harm, in this study a standardised definition of deliberate self harm was used, thereby enabling valid international comparisons with other European countries. The lifetime prevalence of DSH among adolescents in the different regions participating in the CASE study ranged from 4.1% in The Netherlands [12] to 13.2% in the United Kingdom [8]. In this context, the lifetime DSH prevalence of 9.1% among Irish school going adolescents can be considered relatively high. In comparison with prevalence rates reported in international studies using slightly different methodologies and focusing on a broader age range among adolescents, again the prevalence of DSH in Irish adolescents appears to be higher. In a cross-sectional survey among 12 to 15 year olds in the U.S state of Washington, Patton et al. found that 3.7% reported an episode of DSH in the 12 months prior to the survey, which is lower than the 12 month DSH prevalence (5.7%) in the present study [13]. In a general population based survey in Norway among [13][14][15][16][17][18][19] year olds, Groholt et al found a life time DSH prevalence of 8.1%, which is fairly similar to the Irish prevalence [4].

One drawback to the use of this definition is that it is likely to have produced a conservative estimate of deliberate self harm amongst Irish adolescents due to the requirement of validating response to the initial DSH question by a detailed description. In the present study, 104 participants responded positive to the initial DSH question, but  did not provide a detailed description of the self harm act, and were therefore excluded from the analyses.

The current study shows that teenage girls are significantly more likely to harm themselves than teenage boys, which is consistent with a similar study in England. Adolescent girls aged 15 and 16 years were 3.5 times more likely (11.2% vs. 3.2%) to engage in self harm than males of the same age [8]. While this finding has important implications for designing prevention and intervention programs for preventing deliberate self harm and promoting positive mental health, it is important not to neglect adolescent boys as they appear to have the highest risk of taking their life and they are also less likely to talk to someone or seek help if they do have problems [14,15].

Self-cutting was the most common method of deliberate self harm reported by both males and females. This is different compared to the hospital presentations due to DSH by adolescents as monitored by the National Registry of Deliberate Self Harm, where overdose appeared to be the most common method of deliberate self harm [1].

Our findings in relation to the motives for DSH are in line with findings from other studies [16][17][18]. The most frequently reported motives in our study included, 'wanting to get relief from a terrible situation' (78.9%) and 'wanting to die' (60.9%). It is notable that although 'wanting to die' was the second most frequently reported motive, no participant reported this motive as a single motive for DSH, which reflects an ambivalent attitude whereby the expression of feelings of extreme anxiety that the adolescent wishes to escape from prevail. These findings also support the notion that not all instances of DSH are motivated by suicidality.

Conclusion

In conclusion, there is an urgent need to address the issue of deliberate self harm amongst Irish adolescents. Programmes and interventions that raise awareness about positive mental health and help seeking behaviours should be considered. Along with health services finding ways to eliminate the barriers felt by adolescents that may prevent them from seeking help and to make contact with adolescents in a youth friendly medium rather than waiting for adolescents to come to health services.

Table 1 :
1Description of sample and prevalence of DSH by sociodemographic factorsNumber (%)
Prevalence of DSH (95% CI)

Table 4 )
4. Boys more often

Table 2 :
2Prevalence of deliberate self harmSelf report 1
Based on standardised DSH description 2
N/total respondents
% (95%CI)
N/total respondents
% (95%CI)
Lifetime
458/3747
12.2% (11.2%-13.3%)
333/3646
9.1% (8.2% -10.1%)
-More than a year ago
173/3747
4.6% (4.0%-5.4%)
117/3646
3.2% (2.7% -3.9%)
-Past year
266/3747
7.1% (6.3% -8.0%)
208/3646
5.7% (5.0% -6.5%)
-Past month
83/3747
2.2% (1.8% -2.7%)
65/3646
1.8% (1.4% -2.3%)

Students who had thought of harming themselves but did not go through with it
n/total respondents
% (95%CI)

Past Year
807/3732
21.6% (20.3% -23.0%)
Past Month
313/3732
8.4% (7.5% -9.3%)

1 19 did not specify the time of their last DSH act
2 8 did not specify the time of their last DSH act

Table 3 :
3Methods of deliberate self harm by genderSelf cutting
Overdose
Alcohol
Recreational Drugs
Self Battery
Hanging
Other
Total

Girls
174 (68.8%)
89 (35.2%)
10 (4.0%)
5 (2.0%)
7 (2.8%)
5 (2.0%)
11 (4.3%)
253
Boys
45 (57.0%)
19 (24.1%)
6 (7.6)
8 (10.1%)
5 (6.3%)
4 (5.1%)
4 (5.1%)
79
Total
220* (66.0%)
108 (32.4%)
16 (4.8%)
13 (3.9%)
12 (3.6%)
9 (2.7%)
15 (4.5%)
333*

*Gender was unknown in 1 case of self-cutting
Please note: Percentages add up to more than 100 as multiple methods of DSH are reported

Table 4 :
4Motives reported for deliberate self harm by genderFemales (N = 253) %
Males (N = 79) %
Relative Risk (M/F)
95% CI

Table 5 :
5Help seeking behaviour among those who harmed themselves (n = 333)Source of help
Before DSH
After DSH

Family
7.8%
20.5%
Friend
38.2%
40.3%
Teacher
5.8%
6.5%
GP
1.8%
7.7%
Social Worker
3.3%
4.5%
Psychologist/Psychiatrist
4.0%
9.2%
Telephone Helpline
4.4%
1.6%
Drop-in/Advice Centre
1.1%
1.2%
Other
11.2%
7.1%

(page number not for citation purposes)
AcknowledgementsWe would like to thank the National Suicide Review Group and the Ireland Funds who provided funding for this study. We would also like to thank Rachel Farrow and Eric Kelleher who helped with data collection, Dr Helen Keeley for her advice and assistance in data collection, Eileen Williamson for her programme support, the school staff who helped us with the study, the students who participated and Dr Nicola Madge and Dr Erik Jan de Wilde for coordinating the study at international level. The research was conducted in collaboration with the Child and Adolescent Self Harm in Europe (CASE) study.Competing interestsThe author(s) declare that they have no competing interests.Authors' contributionsCM drafted the manuscript and was involved in the data collection and data analysis. PC and IJP were involved in the design of the study. CM and EA were involved in the coordination of the data collection. PC had a leading role in the data analysis. All authors were involved in the interpretation and writing of the final manuscript.Publish with Bio Med Central and every scientist can read your work free of chargePre-publication historyThe pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2458/8/79/prepub
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