A simplified index of physical health for use in epidemiological studies

A battery of simple questions designed to measure physical health, in terms of ability to perform physical activities, was appraised in 1839 men and women aged ⩾ 50 years in a community survey in Jerusalem. The number of “Yes” answers to six questions, five of which could be skipped if the first one was answered positively, was found to be a satisfactory index, with a high degree of consistency-reliability in the total sample (Cronbach's alpha coefficient = 0.97) and in subgroups categorized by sex, age, education, or father's region of birth. The index constituted an excellent Guttman scale (coefficient of reproducibility = 0.96, coefficient of scalability = 0.94), indicating that the score serves both as a measure of physical health and as an indication of the profile of capabilities. Associations with age and other variables conformed with expectations, attesting the construct validity of the index.