. disabilities of the arm , shoulder , and hand ( dash ) questionnaire is a patient - reported outcome measure ( prom ) that measures the magnitude of disability for the upper extremity . it consists of 30 items , 21 of which assess the ability to perform physical activities , 5 items measure pain , and 4 items measure the psychosocial effects . item elimination in order to shorten the questionnaire resulted in an 11-item instrument , which proved to be as reliable as the original dash instrument . retention of the clinically oriented questions in the quick - dash made it a comparable instrument to the full dash questionnaire . the quick - dash is more appealing than the dash because it can be administered in the clinic in a shorter time . a well - translated and adapted questionnaire would facilitate multicenter studies and increases the feasibility of meta - analysis studies . farsi is spoken in several countries including iran , tajikistan , afghanistan , and some regions of pakistan and iraq . validity of the quick - dash has been tested in several other languages . in this study , our aim was to assess the validity and reliability of the persian version of the quick - dash in patients with upper extremity conditions . in total , 202 patients with upper extremity problems enrolled in this study from january 2013 to december 2013 . inclusion criteria were age above 18 years , ability to read and write persian as a mother tongue , and a minimum of 4-week symptom duration [ table 1 ] . at the first visit , all patients responded to the persian quick - dash as well as the persian short form 36 health survey ( sf-36 ) and the michigan hand outcome questionnaire ( mhoq ) [ table 2 ] . to test the reliability , 71 patients accepted to return for the second visit after 3 days to fill the persian quick - dash without receiving any major treatment or changes in symptoms . this study was reviewed and approved by the committee of research and patients consented verbally to participate in the study . characteristics of patients with upper extremity conditions ( n=202 ) average functional score of patients with upper extremity conditoins ( n=202 ) reliability can be test by either measuring the cronbach 's alpha for internal consistency or intra - class correlation coefficient ( icc ) for test - retest reliability ( reproducibility ) . commonly accepted values for cronbach 's alpha are described as excellent for  > 0.9 , good for 0.9 >  > 0.7 , acceptable for 0.7 >  > 0.6 , poor for 0.6 >  > 0.5 , and unacceptable for  < 0.5 . test - retest reliability is tested by administering a questionnaire to a patient on two separate occasions without any substantial changes in his / her symptoms . a correlation coefficient of 0 indicates no reliability , whereas a value of 1 indicates excellent reliability . to measure test - retest reliability in our study , 71 patients randomly filled the persian quick - dash for a 2 time 3 days after the first visit , without being given any major treatment or surgery . to test the construct validity , the new questionnaire is tested against a validated questionnaire with similar or relevant context to assess the correlation between the two questionnaires . we tested the persian quick - dash against the sf-36 questionnaire and mhoq , which have been validated in persian . statistical analysis performed using spss version 11.5 ( spss inc . , chicago , il , usa ) . the sf-36 is an easily administered prom that is frequently used to measure the quality of life . it consists of 36 questions divided into two major domains of physical and mental components , each one consisting of four sub - domains physical function , role - physical , bodily pain , and general health are sub - domains of functional health . vitality , social function , role - emotional and mental health are sub - domains of psychometrical health . it consists of 37 items divided into six subscales , including hand function , pain , activities of daily living , work , esthetics , and patient satisfaction . in total , 202 patients with upper extremity problems enrolled in this study from january 2013 to december 2013 . inclusion criteria were age above 18 years , ability to read and write persian as a mother tongue , and a minimum of 4-week symptom duration [ table 1 ] . at the first visit , all patients responded to the persian quick - dash as well as the persian short form 36 health survey ( sf-36 ) and the michigan hand outcome questionnaire ( mhoq ) [ table 2 ] . to test the reliability , 71 patients accepted to return for the second visit after 3 days to fill the persian quick - dash without receiving any major treatment or changes in symptoms . this study was reviewed and approved by the committee of research and patients consented verbally to participate in the study . characteristics of patients with upper extremity conditions ( n=202 ) average functional score of patients with upper extremity conditoins ( n=202 ) reliability can be test by either measuring the cronbach 's alpha for internal consistency or intra - class correlation coefficient ( icc ) for test - retest reliability ( reproducibility ) . internal consistency measures the consistency of responses across the questionnaire and the subscales . commonly accepted values for cronbach 's alpha are described as excellent for  > 0.9 , good for 0.9 >  > 0.7 , acceptable for 0.7 > > 0.6 , poor for 0.6 >  > 0.5 , and unacceptable for  < 0.5 . test - retest reliability is tested by administering a questionnaire to a patient on two separate occasions without any substantial changes in his / her symptoms . a correlation coefficient of 0 indicates no reliability , whereas a value of 1 indicates excellent reliability . to measure test - retest reliability in our study , 71 patients randomly filled the persian quick - dash for a 2 time 3 days after the first visit , without being given any major treatment or surgery . to test the construct validity , the new questionnaire is tested against a validated questionnaire with similar or relevant context to assess the correlation between the two questionnaires . we tested the persian quick - dash against the sf-36 questionnaire and mhoq , which have been validated in persian . statistical analysis performed using spss version 11.5 ( spss inc . , chicago , il , usa ) . statistical analysis performed using spss version 11.5 ( spss inc . , chicago , il , usa ) . the sf-36 is an easily administered prom that is frequently used to measure the quality of life . it consists of 36 questions divided into two major domains of physical and mental components , each one consisting of four sub - domains physical function , role - physical , bodily pain , and general health are sub - domains of functional health . vitality , social function , role - emotional and mental health are sub - domains of psychometrical health . it consists of 37 items divided into six subscales , including hand function , pain , activities of daily living , work , esthetics , and patient satisfaction . icc was 0.89 , indicating good to excellent test - retest reliability [ table 3 ] . there was a high and significant inverse correlation between the quick - dash and the mhoq , and the sub - domains of the sf-36 , indicating a strong correlation between the quick - dash and the other validated questionnaire in the same domain [ table 4 ] . convergent validity was confirmed , as the spearman correlation between the quick - dash and mhoq was 0.67 and ranged from 0.24 to 0.56 between the sub - domains of the sf-36 and quick - dash [ table 4 ] . internal consistency and test - retest reliability of the farsi version of the quick - dash convergent validity expressed by spearman 's rho correlation coefficient between quick - dash and subdomins of the sf-36 and mhoq the purpose of this study was to establish the validity of the persian version of the quick - dash in patients with upper extremity conditions . our results indicate that farsi quick - dash is a reliable and valid instrument for studying outcomes in patients with upper extremity conditions . in the current study , internal consistency and test - retest reliability indicated the excellent reliability of the farsi version of the quick - dash . testing the construct validity revealed moderate to strong correlation between quick - dash and the mhq and subscales of the sf-36 . first of all , this is a single - center study , which may not represent the general patient population . however , this is a major tertiary referral center , providing care to the entire north east and east , and south east provinces of iran . another limitation was the administration of sf-36 questionnaire , which is more general than quick - dash , and mhoq , which is more specific compared to the quick - dash , to test construct validity ; however , some studies have shown relatively small differences in the responsiveness of the more general and more specific measures of disability . translations of the dash questionnaire are available in most languages ; however , less work has been done in the cross - cultural adaptation of the quick - dash . japanese , and turkish versions , cronbach 's alpha was 0.89 , 0.88 and 0.84 , respectively , showing good internal consistency . similarly , icc was 0.94 , 0.93 , and 0.82 in french , turkish , and japanese versions , respectively , showing good test - retest reliability . in our study , cronbach 's alpha and icc were 0.90 and 0.89 respectively , showing comparable results with previously validated versions , indicating the reliability of our study . we compared the quick - dash with sf-36 and mhoq to test the construct validity , using spearman 's correlation coefficient . in order to test the construct validity of the turkish version of the quick - dash , koldas dogan et al . studied patients with carpal tunnel syndrome using the boston carpal tunnel questionnaire , visual analogue scale - pain ( vas - pain ) , and pinch and grip strength tests to measure the correlation in responsiveness with quick - dash . quick - dash showed moderate correlations with vas - pain and grip strength test , a good correlation with the pinch strength test , and high correlation with boston carpal tunnel questionnaire . the japanese version of the quick - dash was tested against the dash , sf-36 and vas . the correlation coefficients were 0.92 and 0.52 when compared with dash and vas , respectively . in addition , correlations between quick - dash and sf-36 subscales ranged from 0.29 to 0.73 . in a study to validate the french version , the correlation was tested using subjective assessment of activities of daily living ( adl ) , active range of motion ( rom ) , and measurement of abduction strength ( strength ) . correlation of the french quick - dash score with scores for french dash ( r = 0.96 ) , perceived handicap score ( r = 0.79 ) , adl ( r = 0.73 ) , pain during activities ( r = 0.63 ) , strength ( r = 0.58 ) , pain at rest ( r = 0.57 ) , and rom ( r = 0.51 ) indicated good construct validity . in this study , we evaluated the reliability and validity of the persian version of the quick - dash . observation of excellent internal consistency , good to excellent test - retest reliability , and moderate to strong construct validity confirms the validity and reliability of the persian quick - dash in the evaluation of the magnitude of disability for upper extremity conditions .
background : the aim was to assess the validity and reliability of the persian version of shortened disabilities of the arm , shoulder , and hand ( quick - dash ) questionnaire in patients with upper extremity conditions.methods:we administered the persian version of quick - dash to 202 patients with upper extremity conditions , of which 71 patients randomly returned after 3 days to respond to the questionnaire for the 2nd time . in order to test the construct validity of the questionnaire 
 , patients responded to the michigan hand outcome questionnaire ( mhoq ) and short form 36 health survey ( sf-36 ) as well . 
 internal consistency was tested using the cronbach 's alpha , and test - retest reliability was measured using intra - class correlation coefficient ( icc).results : cronbach 's alpha was 0.90 . 
 icc was 0.89 . 
 convergent validity was confirmed , as the spearman correlation between the quick - dash and mhoq was 0.67 and ranged from 0.24 to 0.56 between the subscales of the sf-36 and quick-dash.conclusions:observation of excellent internal consistency , good to excellent test - retest reliability , and moderate to strong construct validity confirms the validity and reliability of the persian version of quick - dash for evaluating the magnitude and level of disability in upper extremity conditions .