In previous studies more questionnaires were used but these were often developed for osteoarthritis [ 12, 13, 26, 27].
In order to obtain more questionnaires from nurses a cluster sampling design was used in the 2009 survey, as described previously [ 11].
HUI data is collected using one or more questionnaires in formats selected to match the specific study design criteria.
In addition, up to six more questionnaires were to be distributed to other cadres such as lab technologists, pharmacists, nutritionists, radiologists, and physiotherapists if available making a maximum sample of 34 per hospital.
Furthermore, it results in more complete questionnaires and a high response rate [ 23].
Of the initial 199 adolescents, 43 were excluded due to missing values (>20%) in one or more questionnaire (see below).
Twenty-three questioners filled in more than one questionnaire (31 questionnaires).
Also, sharp, tingling, dull, throbbing sensations were included in more than five questionnaires (table 1).
Diaries have the advantage of being able to measure exposure time, activities, and mental states in more detail than questionnaires at one point in time.
This allowed for an exploration of both individual and collective perspectives on the meanings attributed to narratives within lectures, and in more depth than questionnaires or surveys alone [ 26].
