MEASUREMENT ISSUES AND RELATED CLASSIFICATIONS
38. The collection of the variable 'Age' is necessary to determine whether or not a 'Core activity need for assistance' exists for persons who respond to the Self-completed collection question on reason for assistance with 'Old or young age'. If the person's age is 40 years or more a need for assistance does exist.
39. In most circumstances the determination of 'Core activity need for assistance' is dependent on respondent perception of their need for help, and their interpretation of the meanings of 'help', 'supervision', 'difficulty', 'restriction', and 'everyday activity'. No other specific measurement issues apply to the variable 'Core activity need for assistance' beyond the normal constraints affecting statistical collections, such as problems with confidentiality or standard errors which may not permit the output of some data.
40. The classification for 'Severity of disability' is used to derive profound or severe core activity limitation relatable to 'Core activity need for assistance' when using the interviewer-based collection module.