The Dutch Shoulder Disability Questionnaire with 16 questions is a medium-length questionnaire and is also easy to use.
However, a full-length questionnaire still under development – the Infant/Toddler Quality of Life Questionnaire (ITQOL) – was made available for purposes of further evaluation (9).
To determine whether a shortened questionnaire may be used to replace an existing full-length questionnaire, several assessments can be performed to show that the short version should be measuring what the original version is measuring.
The main outcome measure was a new full-length questionnaire consisting of 3 global items and 10 multi-item scales constructed to measure the physical and emotional well-being of toddlers and their families.
As will be explained in the Methods section, curtailment and stochastic curtailment attempt to shorten each respondent's questionnaire while maintaining the same test outcome ("positive" or "negative") that would have been made if the full-length questionnaire had been used.
Moreover, the fatigue scales that are frequently used are traditional, fixed-length questionnaires, meaning that each patient has to fill in the same items in the same order.
To obtain adequate response rates, we applied methodologies suggested in the literatures [22], [23], including factors such as length of questionnaire, traditional mail survey (as opposed to internet-based survey), providing return envelopes and follow-up mailing with replacement questionnaires.
The strength of order effects (if any) may depend on the length of questionnaire.
It may well relate to the length of questionnaire and the context of the study.
