Assessment of the methodological quality with COSMIN criteria.

COSMIN psychometric property boxes: A = internal consistency, B = reliability, C = measurement error, D = content validity, E = structural validity, F = hypotheses testing, G = cross-cultural validity, H = criterion validity, I = responsiveness. 4-point scale rating: +++ = excellent, ++ = good, + = fair, 0 = poor, empty space = COSMIN rating not applicable. For exact information regarding the definitions of psychometric properties and 4-point scale rating see COSMIN website (www.cosmin.nl). a = Test-Retest-Reliability, b = Inter-rater-Reliability, c = Intra-rater-Reliability, d = only evaluation of the quality of the translation procedure, p = patient version, ph = physician version. Assessment of the methodological quality with COSMIN criteria.