Informed consent: II. Withdrawal-without-prejudice clauses may increase no-shows

Area of Science:

• Psychology
• Research Methodology
• Participant Recruitment

Background:

• Understanding factors influencing participant recruitment and retention is crucial for research validity.
• The timing of information disclosure, such as withdrawal clauses, may impact participant engagement.

Purpose of the Study:

• To investigate the effect of the timing of informing participants about the withdrawal-without-prejudice clause on study attendance.
• To examine whether this timing influences participant persistence on a cognitive task.
• To explore differences between no-shows and appointment keepers in locus of control and academic performance.

Main Methods:

• 132 undergraduate volunteers were randomly assigned to receive information about the withdrawal clause either at recruitment or immediately before testing.
• Study attendance rates were recorded.
• Participant performance on a persistence-measuring test was assessed.
• Locus of control and grade point averages were compared between attendees and no-shows.

Main Results:

• A significantly higher no-show rate (50%) was observed when participants were informed of the withdrawal clause at recruitment compared to when informed just before testing (27%).
• No significant difference in performance on the persistence test was found between the two groups.
• No-shows exhibited a more external locus of control regarding academic matters and had lower grade point averages than appointment keepers.

Conclusions:

• The timing of disclosing the withdrawal-without-prejudice clause critically affects participant attendance in research studies.
• Informing participants earlier about withdrawal rights can lead to decreased participation rates.
• Participant characteristics, such as locus of control and academic achievement, are associated with appointment keeping.