title: Quality of life and hospital re-admission in patients with chronic obstructive pulmonary disease. Structured exercise improves physical functioning in women with stages I and II breast cancer: results of a randomized controlled trial. Quality of life in patients with chronic obstructive pulmonary disease improves after rehabilitation at home. Randomized comparison of four tools measuring overall quality of life in patients with advanced cancer. Defining the minimum level of detectable change for the Roland-Morris questionnaire. Short- and long-term effects of outpatient rehabilitation in patients with chronic obstructive pulmonary disease: a randomized trial. What are minimal important changes for asthma measures in a clinical trial? Quality of life in patients with endoscopy-negative heartburn: reliability and sensitivity of disease-specific instruments Using the standard error of measurement to identify important changes on the Asthma Quality of Life Questionnaire Long term benefits of rehabilitation at home on quality of life and exercise tolerance in patients with chronic obstructive pulmonary disease. Linking clinical relevance and statistical significance in evaluating intra-individual changes in health-related quality of life. What is a clinically meaningful change on the Functional Assessment of Cancer Therapy-Lung (FACT-L) Questionnaire? Results from Eastern Cooperative Oncology Group (ECOG) Study 5592. Measurement of fatigue. determining minimally important clinical differences. Interpreting quality-of-life clinical trial data for use in the clinical practice of antihypertensive therapy. Quality of life of women with urinary incontinence: further development of the incontinence quality of life instrument (I-QOL) Minimal clinically important rehabilitation effects in patients with osteoarthritis of the lower extremities. Smallest detectable and minimal clinically important differences of rehabilitation intervention with their implications for required sample sizes using WOMAC and SF-36 quality of life measurement instruments in patients with osteoarthritis of the lower extremities. Quality of life changes in COPD patients treated with salmeterol.
abstract: BACKGROUND There is some evidence that quality of life ( QOL ) in patients with chronic obstructive pulmonary disease ( COPD ) may predict clinical outcomes and use of re sources . This study examined whether QOL scores could prospect ively predict re-admission for COPD or death within 12 months of an original admission , and whether QOL scores predicted home nebuliser provision . METHODS The study was carried out in all acute medical wards of Aberdeen Royal Infirmary , Woodend and City Hospitals , Aberdeen over 12 months . A total of 377 patients admitted with an exacerbation of COPD were identified in this time , 111 of whom were not included in the study because they refused the interview or died before discharge . The remaining 266 patients completed the St George 's Respiratory Question naire ( SGRQ ) . Information on spirometric parameters , nebuliser provision at discharge , provision of domiciliary oxygen , and re-admission within 12 months was collected from patient notes . RESULTS The mean age of the patients was 68 years and 53 % were men . The mean ( SD ) forced expiratory volume in one second ( FEV1 ) was 38.8 (18.0)% predicted and forced vital capacity ( FVC ) was 58.9 (23.8)% predicted . Higher ( worse ) scores on the SGRQ were significantly related to re-admission for COPD in the next 12 months ( difference = 4.8 , 95 % CI 1.6 to 8.0 ) . Patients who were re-admitted and died from COPD did not differ in SGRQ scores from those who were re-admitted and survived for more than 12 months . Re-admission was not related to sex , age , or pulmonary function . One hundred and thirty eight patients did not have a home nebuliser before admission . Of these , 14 were provided with a home nebuliser at discharge . Patients provided with nebulisers had significantly worse SGRQ scores and worse FVC . The 41 patients given domiciliary oxygen did not differ in SGRQ or spirometric parameters . Logistic regression analysis of the three SGRQ subscales ( Symptom , Impact and Activity ) , adjusting for lung function , age and sex , showed that all three subscales were significantly related to hospital readmission and that Impact scores were related to nebuliser provision . Women did not differ from men in Symptom scores on the SGRQ but differed markedly on the Activity and Impact scales . CONCLUSIONS It is concluded that poor scores on the SGRQ , a QOL scale which measures patient distress and coping , are associated with re-admission for COPD and use of re sources such as nebulisers , independent of physiological measures of disease severity PURPOSE Self-directed and supervised exercise were compared with usual care in a clinical trial design ed to evaluate the effect of structured exercise on physical functioning and other dimensions of health-related quality of life in women with stages I and II breast cancer . PATIENTS AND METHODS One hundred twenty-three women with stages I and II breast cancer completed baseline evaluations of generic and disease- and site-specific health-related quality of life , aerobic capacity , and body weight . Participants were r and omly allocated to one of three intervention groups : usual care ( control group ) , self-directed exercise , or supervised exercise .  Quality of life , aerobic capacity , and body weight measures were repeated at 26 weeks . The primary outcome was the change in the Short Form-36 physical functioning scale between baseline and 26 weeks . RESULTS Physical functioning in the control group decreased by 4.1 points , whereas it increased by 5.7 points and 2.2 points in the self-directed and supervised exercise groups , respectively ( P = .04 ) . Post hoc analysis showed a moderately large ( and clinical ly important ) difference between the self-directed and control groups ( 9.8 points ; P = .01 ) and a more modest difference between the supervised and control groups ( 6.3 points ; P = .09 ) . No significant differences between groups were observed for changes in quality of life scores . In a secondary analysis of participants stratified by type of adjuvant therapy , supervised exercise improved aerobic capacity ( + 3.5 mL/kg/min ; P = .01 ) and reduced body weight ( -4.8 kg ; P < .05 ) compared with usual care only in participants not receiving chemotherapy . CONCLUSION Physical exercise can blunt some of the negative side effects of breast cancer treatment , including reduced physical functioning .  Self-directed exercise is an effective way to improve physical functioning compared with usual care . In participants not receiving chemotherapy  , supervised exercise may increase aerobic capacity and reduce body weight compared with usual care We have developed a rehabilitation programme at home and have investigated its effects on quality of life ( QOL ) , lung function , and exercise tolerance in patients with chronic obstructive pulmonary disease ( COPD ) . We studied 43 patients with severe airflow obstruction : forced expiratory volume in one second ( FEV1 ) 1.3 + /- 0.4 l ( mean + /- SD ) , FEV1/inspiratory vital capacity ( IVC ) 37 + /- 7.9 % . After stratification , 28 patients were r and omly allocated in a home rehabilitation programme for 12 weeks . Fifteen patients in a control group received no rehabilitation . The rehabilitation group received physiotherapy by the local physiotherapist , and supervision by a nurse and a general practitioner .  Quality of life was assessed by the four dimensions of the Chronic Respiratory Question naire ( CRQ ) . We found a highly significant improvement in the rehabilitation group compared to the control group for the dimensions dyspnoea , emotion , and mastery . Lung function showed no changes in the rehabilitation group . The exercise tolerance improved significantly in the rehabilitation group compared to the control group . The improvement in quality of life was not correlated with the improvement in exercise tolerance . Rehabilitation of COPD patients at home may improve quality of life ; this improvement is not correlated with an improvement in lung function and exercise tolerance PURPOSE We report on a clinical trial developed to compare four different instruments that provide overall quality -of-life ( QOL ) scores , ranging from a simple , one-item instrument to more detailed instruments . Two issues addressed were ( 1 ) Will QOL tools suffer from missing data when used in a community-based cooperative group setting ? , and ( 2 ) Are there additional data generated by a more detailed multiitem instrument over that provided by a single-item global QOL question ? MATERIAL S AND METHODS A four-arm r and omized trial was design ed to compare four instruments that provide overall QOL scores in patients with advanced colorectal cancer . Patients and physicians completed the single-item Spitzer Uniscale ( UNISCALE ) at baseline and monthly . Patients were r and omly assigned to complete , in addition , either the 22-item Functional Living Index-Cancer ( FLIC ) , the five-item Spitzer QOL index ( QLI ) , a picture-face scale ( PICT ) , or nothing else . RESULTS A total of 128 patients were r and omized . Greater than 90 % complete QOL data were obtained . There was strong correlation , concordance , and criterion-related validity among all four patient-completed tools . The UNISCALE had a greater decrease over time than did the FLIC ( P=.005 ) , which suggests a greater sensitivity ; the UNISCALE was similar to the QLI and the PICT in this regard . Physicians provided lower UNISCALE scores than patients . Results supported the hypothesis that QOL is prognostic for survival . CONCLUSION Patients can effectively complete QOL tools in a cooperative group setting with proper education of health care providers and patients . A simple single-item tool ( UNISCALE ) appears to be appropriate to obtain a measure of overall QOL BACKGROUND AND PURPOSE The Rol and -Morris Question naire ( RMQ ) is a self-administered disability measure in which greater levels of disability are reflected by higher numbers on a 24-point scale . The RMQ has been shown to yield reliable measurements , which are valid for inferring the level of disability , and to be sensitive to change over time for groups of patients with low back pain . Little is known about the usefulness of this instrument in aiding decision making regarding individual patients . The purpose of this study was to determine the minimum level of detectable change when the RMQ is applied to individual patients . SUBJECTS The study sample consisted of 60 out patients with low back pain . METHODS The RMQ was administered at the subjects ' initial visit and again 4 to 6 weeks later . Conditional st and ard errors of measurement ( CSEMs ) were computed for initial and follow-up RMQ scores , and these values were used to estimate the minimum level of detectable change . Results . Minimum levels of detectable change at the 90 % confidence level varied from 4 to 5 RMQ points . CONCLUSION AND DISCUSSION The magnitude of CSEMs is sufficiently small to detect change in patients with initial scores in the central portion of the scale ( 4 - 20 RMQ points ) ; however , the magnitude is too large to detect improvement in patients with scores of less than 4 and deterioration in patients who have scores greater than 20 PURPOSE Pulmonary rehabilitation programs are effective in patients with severe chronic obstructive pulmonary disease ( COPD ) in the short term , but their long-term effects are not known . We investigated the short- and long-term effects of a 6-month outpatient rehabilitation program in patients with severe COPD . SUBJECTS AND METHODS One hundred patients were r and omly assigned to receive either an exercise training program that included cycling , walking , and strength training ( n = 50 ) or usual medical care ( n = 50 ) . Thirty-four patients in the training group were evaluated after 6 months ( end of training ) , and 26 were evaluated after 18 months of follow-up . In the control group , 28 patients were evaluated at 6 months and 23 after 18 months . We measured pulmonary function , 6-minute walking distance , maximal exercise capacity , peripheral and respiratory muscle strength , and quality of life ( on a 20 to 140-point scale ) , and estimated the cost-effectiveness of the program . RESULTS At 6 months , the training group showed improvement in 6-minute walking distance [ mean difference ( training - control ) of 52 m ; 95 % confidence interval ( CI ) , 15 to 89 m ] , maximal work load ( 12 W ; 95 % CI , 6 to 19 W ) , maximal oxygen uptake ( 0.26 liters/min ; 95 % CI , 0.07 to 0.45 liters/min ) , quadriceps force ( 18 Nm ; 95 % CI , 7 to 29 Nm ) , inspiratory muscle force ( 11 cm H(2)O ; 95 % CI , 3 to 20 cm H(2)O ) , and quality of life ( 14 points ; 95 % CI , 6 to 21 points ; all P < 0.05 ) . At 18 months all these differences persisted ( P < 0.05 ) , except for inspiratory muscle strength . For 6-minute walking distance and quality of life , the differences between the training group and controls at 18 months exceeded the minimal clinical ly-important difference . CONCLUSION Among patients who completed the 6-month program , outpatient training result ed in significant and clinical ly relevant changes in 6-minute walking distance , maximal exercise performance , peripheral and respiratory muscle strength , and quality of life . Most of these effects persisted 18 months after starting the program In this study , the perceptions of asthmatics to change in their disease was associated with observed changes in clinical asthma measures , in order to identify the threshold where changes in clinical asthma measures are perceivable by patients . The study included 281 asthmatic patients , aged 18 - 63 yrs , in a r and omized , placebo-controlled clinical trial of a leukotriene antagonist .  Changes were related in : 1 ) asthma symptom scores ; 2 ) inhaled beta-agonist use ; 3 ) forced expiratory volume in one second ( FEV1 ) ; and 4 ) peak expiratory flow ( PEF ) to a global question that queried overall change in asthma since starting the study drug . Additional analyses examined differences in the group reporting minimal improvement by treatment ( active treatment versus placebo ) , sex and age groups . The average minimal patient perceivable improvement for each measure was : 1 ) -0.31 points for the symptom score on a scale of 0 - 6 ; 2 ) -0.81 puffs x day(-1 ) for inhaled beta-agonist use ; 3 ) 0.23 L for FEV1 ; and 4 ) 18.79 L x min(-1 ) for PEF . In general placebo-treated patients and older patients , who reported minimal improvement , experienced less mean improvement from baseline than active-treated patients and younger patients , who reported minimal improvement . Determining the minimal patient perceivable improvement value for a measure may be helpful to interpret changes . However , interpretation should be carried out cautiously when reporting a single value as a clinical ly important change OBJECTIVES : Endoscopy-negative gastroesophageal reflux disease ( GERD ) lacks objective markers of disease severity . Evaluation of therapies for GERD must therefore rely on subjective measures , including patient self-report question naires , to measure the clinical effectiveness of therapeutic interventions . We aim ed to evaluate the previously vali date d Gastrointestinal Symptoms Rating Scale ( GSRS ) and the Quality of Life in Reflux and Dyspepsia ( QOLRAD ) question naires for reliability and responsiveness to change over time . METHODS : Patients ( n = 1143 ) with heartburn , but no esophagitis included in a r and omized clinical trial assessing the effectiveness of active treatment with proton pump inhibitors over 4 wk were evaluated . RESULTS : The test-retest reliability of both question naires over time was good to excellent ( GSRS 0.53–0.69 ; QOLRAD 0.65–0.76 ) , as was the responsiveness estimated by st and ardized response means ( GSRS reflux dimension , −1.43 ; QOLRAD 0.81–1.43 ) and effect sizes ( GRSR reflux dimension , −1.74 ; QOLRAD 0.82–1.56 ) . The relationship between improvement in the GSRS reflux dimension score and the amount of clinical benefit as estimated by the patients themselves ( based on the Overall Treatment Evaluation ) suggested a minimally clinical relevant change is 0.5 on the seven grade d scales applied . The importance rating indicated that an important change in the GSRS reflux dimension and the QOLRAD dimensions is equivalent to 1.0 , and a very important change to 1.5 . CONCLUSIONS : The GSRS and QOLRAD are valid question naires that are reliable and sensitive to change . Both question naires should be suitable for use in clinical trials of therapeutic interventions for patients with heartburn Objectives : To establish a link between the minimal important difference ( MID ) and the st and ard error of measurement ( SEM ) for all responsive dimensions of the Asthma Quality of Life Question naire ( AQLQ ) . Methods : Secondary data analysis of baseline and follow-up interview data from 198 out patients with asthma enrolled in a r and omized controlled trial and receiving care at a major urban academic medical center 's general medicine clinics . Domain statistics for baseline and follow-up interviews were examined for the AQLQ . The baseline SEM values were compared with established AQLQ MID st and ards using weighted κ values . Results : One SEM identified the MID in responsive AQLQ dimensions . Weighted κ values ( 0.88–0.93 ) vali date d excellent agreement between these two criteria . Conclusion : This is the third study to support using one SEM to identify important individual change in health-related quality of life ( HRQoL ) measures . However , refinement of the process for determining a measure 's clinical ly meaningful differences is still needed to secure a link between the SEM and the identification of relevant HRQoL change over time BACKGROUND --Pulmonary rehabilitation has been shown to have short term subjective and objective benefits for patients with chronic obstructive pulmonary disease ( COPD ) . However , appropriately controlled studies have not previously been performed , nor have the benefits of different types of continuation programme for rehabilitation been investigated . Both these problems have been addressed in a single study of the long term effects of once monthly physiotherapy versus once weekly physiotherapy at home after a comprehensive home rehabilitation programme on quality of life and exercise tolerance in patients with COPD . METHODS --Thirty six patients with severe airways obstruction ( mean SD ) forced expiratory volume in one second ( FEV1 ) 1.3(0.4 ) 1 , FEV1/inspiratory vital capacity ( IVC ) 37.2(7.9)% ) were studied . Twenty three patients followed a rehabilitation programme at home for 18 months consisting of physiotherapy and supervision by a nurse and general practitioner . During the first three months all 23 patients visited the physiotherapist twice a week for a 0.5 hour session . Thereafter , 11 patients ( group A ) received a session of physiotherapy once weekly while 12 patients ( group B ) received a session of physiotherapy once a month . The control group C ( 13 patients ) received no rehabilitation at all .  Quality of life was assessed by the Chronic Respiratory Question naire , exercise tolerance by the six minute walking distance , and lung function by FEV1 and IVC . Outcome measures were assessed at baseline and at three , six , 12 , and 18 months . RESULTS --Long term improvements in quality of life were found in patients in groups A and B , but not in those in group C compared with baseline , but these only reached significance in group B at all time points . Patients in group B had a higher quality of life than those in group C only at three and 12 months . There was a decrease in both six minute walking distance ( at 12 and 18 months ) and IVC ( at three , 12 , and 18 months ) in patients in group C compared with the baseline measurement . Between groups analysis showed no differences for six minute walking distance , FEV1 , and IVC . CONCLUSIONS --This study is the first to show that rehabilitation at home for three months followed by once monthly physiotherapy sessions improves quality of life over 18 months . The change in quality of life was not associated with a change in exercise tolerance OBJECTIVE To compare the st and ard error of measurement ( SEM ) with established st and ards for clinical ly relevant intra-individual change in an evaluation of health-related quality of life . DESIGN Secondary analysis of data from a r and omized controlled trial . SUBJECTS Six hundred and five out patients with a history of cardiac problems attending the general medicine clinics of a major academic medical center . MEASURES Baseline and follow-up interviews included a modified version of the Chronic Heart Failure Question naire ( CHQ )  and the SF-36 .  The SEM values corresponding to established st and ards for minimal clinical ly important differences ( MCIDs ) on the CHQ were determined . Individual change on the SF-36 was explored using the same SEM criterion . RESULTS One-SEM changes in this population corresponded well to the patient-driven MCID st and ards on all CHQ dimensions ( weighted kappas ( 0.87 ; P < 0.001 ) . The distributions of out patients who improved , remained stable , or declined ( defined by the one-SEM criterion ) were generally consistent between CHQ dimensions and SF-36 subscales . CONCLUSIONS The use of the SEM to evaluate individual patient change should be explored among other health-related quality of life instruments with established st and ards for clinical ly relevant differences . Only then can it be determined whether the one-SEM criterion can be consistently applied as a proxy for clinical ly meaningful change To assess the impact of disease and treatment on patients with advanced non-small cell lung cancer ( NSCLC ) , we set out to determine a clinical ly meaningful change ( CMC ) on the Lung Cancer Subscale ( LCS ) and the Trial Outcome Index ( TOI ) of the Functional Assessment of Cancer Therapy-Lung ( FACT-L ) question naire . We used data from Eastern Cooperative Oncology Group study 5592 ( E5592 ) , a r and omized trial comparing three chemotherapeutic regimens in 599 advanced NSCLC patients . Patients completed the FACT-L at baseline ( pretreatment ) , 6 weeks , 12 weeks , and 6 months . Comparing across baseline performance status ( 0 vs. 1 ) , prior weight loss ( < 5 % vs. > or = 5 % ) , and primary disease symptoms ( < or = 1 vs. > 1 ) , LCS and TOI score differences ranged from 2.4 to 3.6 and 6.5 to 9.2 , respectively ( all Ps < .001 ) . Mean improvement in LCS score from baseline to 12 weeks was 2.4 points in patients who had responded to treatment versus 0.0 points in patients who had progressive disease . Twelve-week LCS change scores for patients progressing early were 3.1 points worse than those of patients progressing later ( mean = -1.2 vs.1.9 , respectively ) . Similarly , the average TOI change score from baseline to 12 weeks was -6.1 for patients who had progressive disease versus -0.8 points for patients who had responded to treatment . Twelve-week TOI change scores for patients progressing early ( mean = -8.1 ) were 5.7 points worse than those of patients progressing later ( mean = -8.1 vs. -2.4 , respectively ) . Analyses assuming nonr and om missing data result ed in slightly larger differences . Clinical ly relevant change scores were estimated as two to three points for the LCS and five to seven points for the TOI , setting upper limits for minimal CMCs . These values were comparable to suggested distribution-based criteria of a minimally important difference . These results support use of a two to three point change in the LCS and five to six point change on the TOI of the FACT-L as a CMC , and offer practical direction for inclusion of important patient-based endpoints in lung cancer clinical trials The purpose was to determine the minimally important clinical difference ( MICD ) in fatigue as measured by the Profile of Mood States , Schwartz Cancer Fatigue Scale ( SCFS ) , General Fatigue Scale , and a 10-point single-item fatigue measure . The MICD is the smallest amount of change in a symptom ( e.g. , fatigue ) measure that signifies an important change in that symptom . Subjects rated the degree of change in their fatigue over 2 days on a Global Rating Scale . 103 patients were enrolled on this multisite prospect i ve repeated measures design . MICD was determined following established procedures at two time points . Statistically significant changes were observed for moderate and large changes in fatigue , but not for small changes . The scales were sensitive to increases in fatigue over time . The MICD , presented as mean change , for each scale and per item on each scale is : POMS = 5.6 , per item = 1.1 , SCFS = 5.0 , per item = 0.8 , GFS = 9.7 , per item = 1.0 , and the single item measure of fatigue was 2.4 points . This information may be useful in interpreting scale scores and planning studies using these measures The use of  quality -of-life indices  in therapeutic trials is gaining recognition as important outcome variables for evaluating the total impact of antihypertensive therapy . While the statistical significance of treatment differentials in  quality -of-life indices  has been well documented , their clinical relevance still remains unclear . The interpretation of clinical trial quality -of-life treatment differentials depends on a clear underst and ing of the normal variability in the index due to changes in day-to-day living and the relationship between the size of the differential and shifts in population responses . Using the results from a large-scale r and omized clinical trial on  quality of life  and  antihypertensive therapy  , a rationale for the interpretation of clinical trial results for use by the practicing clinician is presented OBJECTIVES To report on the further development of the Incontinence Quality of  Life Instrument ( I-QOL ) , a self-report quality of life measure specific to urinary incontinence ( UI ) , including its measurement model , responsiveness , and effect size . METHODS Incontinent female patients ( 141 with stress , 147 with mixed UI ) completed the I-QOL and comparative measures at screening , pretreatment , and four subsequent follow-up visits during participation in a multicenter , double-blind , placebo-controlled , r and omized trial assessing the efficacy of duloxetine . Psychometric testing followed st and ardized procedures . RESULTS Factor analysis confirmed an overall score and three subscale scores ( avoidance and limiting behaviors , psychosocial impacts , and social embarrassment ) . All scores were internally consistent ( alpha = 0.87 to 0.93 ) and reproducible ( ICC = 0.87 to 0.91 ) . The pattern of previously reported correlations with the Short-Form 36-item Health Survey and Psychological Well-Being Schedule were confirmed . Responsiveness statistics using changes in the independent measures of stress test pad weight , number of incontinent episodes , and patient global impression of improvement ranged from 0.4 to 0.8 . Minimally important changes ranged from 2 % to 5 % in association with these measures and effect sizes . CONCLUSIONS In a clinical trial , the I-QOL proved to be valid , reproducible , and responsive to treatment for UI in women OBJECTIVE To estimate minimal clinical ly important differences ( MCID ) of effects measured by the Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) in patients with osteoarthritis ( OA ) of the lower extremities undergoing a comprehensive inpatient rehabilitation intervention . METHODS A prospect i ve cohort study assessed patients ' health by the WOMAC at baseline ( entry into the clinic ) and at the 3 month followup , and by a transition question naire asking about the change of " health in general related to the OA joint " during that time period . The WOMAC section score differences between the " equal " group and the " slightly better " and " slightly worse " groups result ed in the MCID for improvement and for worsening . RESULTS In total 192 patients were followed up . The MCID for improvement ranged from 0.80 to 1.01 points on the continuous WOMAC numerical rating scale from 0 to 10 , reflecting changes of 17 to 22 % of baseline scores . The MCID for worsening conditions ranged from 0.29 ( 6 % ) to 1.03 points ( 22 % ) . In the transition reply subjectively unchanged patients reported a " pessimistic bias " of 0.35 to 0.51 points , except for the stiffness section . Both MCID and pessimistic bias showed regression to the mean and baseline dependency . CONCLUSION The assessment of MCID using the transition method is a heuristic and valid strategy to detect particular rehabilitation effects in patients with OA of the lower extremities with the use of the WOMAC , and it is worth implementing . The size of the MCID and of the systematic bias is comparable to that assessed by other methods and in other therapeutic setting OBJECTIVE To discuss the concepts of the minimal clinical ly important difference ( MCID ) and the smallest detectable difference ( SDD ) and to examine their relation to required sample sizes for future studies using concrete data of the condition-specific Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) and the generic Medical Outcomes Study 36-Item Short Form ( SF-36 ) in patients with osteoarthritis of the lower extremities undergoing a comprehensive inpatient rehabilitation intervention . METHODS  SDD and MCID  were determined in a prospect i ve study of 122 patients before a comprehensive inpatient rehabilitation intervention  and at the 3-month followup .  MCID was assessed by the transition method . Required SDD and sample sizes were determined by applying normal approximation and taking into account the calculation of power . RESULTS In the WOMAC sections the SDD and MCID ranged from 0.51 to 1.33 points ( scale 0 to 10 ) , and in the SF-36 sections the SDD and MCID ranged from 2.0 to 7.8 points ( scale 0 to 100 ) . Both question naires showed 2 moderately responsive sections that led to required sample sizes of 40 to 325 per treatment arm for a clinical study with unpaired data or total for paired followup data . CONCLUSION In rehabilitation intervention , effects larger than 12 % of baseline score ( 6 % of maximal score ) can be attained and detected as MCID by the transition method in both the WOMAC and the SF-36 . Effects of this size lead to reasonable sample sizes for future studies lying below n = 300 . The same holds true for moderately responsive question naire sections with effect sizes higher than 0.25 . When design ing studies , assumed effects below the MCID may be detectable but are clinical ly meaningless Changes in health-related quality of life ( HRQoL ) were evaluated in patients with chronic obstructive pulmonary disease ( COPD ) following treatment with placebo , salmeterol 50 microg twice a day or 100 microg twice a day by metered-dose inhaler . Patients completed the disease-specific St. George 's Respiratory Question naire ( SGRQ ) and the Medical Outcomes Study Short Form 36 ( SF-36 ) at baseline and after 16 wk of treatment . Data from 283 patients ( 95 patients in the placebo group and 94 in each salmeterol group ) were available for HRQoL analysis . Apart from a small difference in ages , all treatment groups were well matched at baseline in terms of forced expiratory volume in one second ( FEV1 ) and HRQoL scores . Compared with placebo , salmeterol 50 microg twice a day was associated with significant improvements in SGRQ " Total " and " Impacts " scores which exceeded the threshold for a clinical ly significant change . This was not seen with salmeterol 100 microg twice a day . Changes in SGRQ and SF-36 scores correlated . They also showed a weak but significant relationship with FEV1 . This study has shown that a modest change in lung function may be associated with clinical ly significant gain in health and well-being in COPD patients
target: There was no consistent relationship with factors such as disease-specific or generic instrument or the number of response options .
  Negative changes were not associated with larger ESs .
  Population -based estimation procedures and brief follow-up were associated with smaller ESs , and acute conditions with larger ESs .
background: Background .
  A number of studies have computed the minimally important difference ( MID ) for health-related quality of life instruments .
  To determine whether there is consistency in the magnitude of MID estimates from different instruments .