The phrase "age at questionnaire" is not entirely correct and may be unclear in written English.
It could be used in contexts where you are referring to the age of a participant at the time they completed a questionnaire, but it lacks clarity.
Example: "The study analyzed the responses based on the age at questionnaire to determine trends among different age groups."
Alternatives: "age during the questionnaire" or "age at the time of the questionnaire".
Among participants with diabetes, duration of diabetes was calculated from age at diagnosis and age at questionnaire completion.
Older age at questionnaire completion was a significant predictor of the proportion of disagreement in the test-retest reliability study.
Ceiling effects decreased with increase in age at questionnaire completion, particularly in the physical health related scales (Table 1).
We determined the effect of characteristics of the centre and child on response, age at questionnaire completion, and response to child drawing tasks.
Independent variables included age at questionnaire, ethnicity, education, household income, marital status, health insurance, level of concern regarding their future health, and gender (limited to health behavior analyses).
Third, to minimize the confounding effect of child's age at questionnaire completion on developmental outcomes, we restricted analyses to children aged 36 to 40 months.
The MFQ was completed by ALSPAC study members at research clinics at ages 10.5 and 13 years and by postal questionnaire at 16 years; slight variations in actual ages at questionnaire completion were unrelated to levels of depressive symptoms.
† Age was calculated based on the age at baseline questionnaire completion.
Compared with individuals aged 16 24 at questionnaire completion, the risk for reporting mental health dysfunction in all three questions increased linearly with age (all Ptrend<0.01).
Among those aged 25 34 and 35 44 at questionnaire completion, significantly higher mental health dysfunction was reported, compared with the general population sample, in relation to six questions (questions 5a, 6, 9b, 9c, 9f, and 9j).
Participants contributed study time from age in 2001, with return of the Violence Questionnaire, through age at the last returned questionnaire, diagnosis of type 2 diabetes, death, or June 2007.
