On the validity of the Middlesex Hospital Questionnaire: a comparison of diagnostic self-ratings in psychiatric out-patients, general practice patients, and 'normals' based on the Hebrew version.

The short clinical diagnostic self-rating scale for psycho-neurotic patients (The Middlesex Hospital Questionnaire) was translated into everyday Hebrew and tested on 216 subjects for: (1) concurrent validity with clinical diagnoses; (2) discriminatory validity on a psychoneurotic gradient of psychiatric out-patients, general practice patients, and normal controls; (3) validity of subscales and discrete items using matrices of Spearman rank correlation coefficients; (4) construct validity using Guttman's smallest space analysis based on coefficients of similarity. The Hebrew MHQ was found to retain its validity and to be easily applicable in waiting-room situations. It is a useful method for generating and substantiating hypotheses on psychosomatic and psychosocial interrelationships. The MHQ seems to enable the expression of the 'neurotic load' of a general practice subpopulation as a centile on a scale, thereby corroborating previous epidemiological findings on the high prevalence of neurotic illness in general practice. There is reason to believe that the MHQ is a valid instrument for the analysis of symptom profiles of subjects involved in future drug trials.