The criterion validity (degree to which the questionnaire measures the true situation) and responsiveness of these questionnaires is hard to assess.
Exclusion criteria consisted of terminally ill patients, dementia or cognitive impairment, inability to fill in Dutch questionnaires, and hard drug or alcohol abusers.
Validated scales, where available, will be used to measure self- reported psychological wellbeing and engagement in behaviour change: anxiety; depression; self- efficacy and readiness to change behaviour will be measured at enrolment and at 36 weeks gestation using questionnaires in hard copy.
Depending on the availability of an e-mail account supported by the company, outcome measures are collected either by online questionnaire or by hard copy questionnaires.
A questionnaire in hard-copy format was used to assess psychosocial functioning, cancer-related knowledge, treatment decision-making roles and information needs.
Participants came into the lab before work (between 8 a.m. and 9.30 a.m). to collect heart rate monitors, salivettes, gum (in the gum condition), and questionnaires (if using hard copies).
If companies prefer hard copy questionnaires, the questionnaires are sent to the department managers, who hand out the questionnaires to the workers.
Several methods exist for collecting data, including hard copy questionnaires, on-line questionnaires (including text messaging), face-to-face interviews and telephone interviews.
Data from the hard copy questionnaires were entered into the online questionnaire format.
Hard copy questionnaires were delivered to all except two participants who received theirs via email.
