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Post-Hoc Enthusiasm and Wariness

Post-Hoc Enthusiasm and Wariness

Status
Not yet recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05686889
Acronym
PHEW
Enrollment
100
Registered
2023-01-17
Start date
2023-05-01
Completion date
2028-09-01
Last updated
2023-01-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Health Behavior

Brief summary

The post-hoc fallacy (also termed the post-hoc-ergo-propter-hoc fallacy) has been recognized for centuries with endless relevance. The general concept in medical care is that patients who improve after a treatment are not necessary patients who improve because of a treatment. Modern medicine provides multiple opportunities to examine such pitfalls of judgment due to the prevailing uncertainty, incompleteness of our understanding pathogenic mechanisms, and natural tendency to connect treatments to outcomes. In this study, we will investigate whether judgments about vitamin supplementation might demonstrate the post-hoc fallacy.

Detailed description

We plan to conduct a brief survey of pharmacies portraying a patient in two slightly different versions. One version will portray the patient who feels better after starting a vitamin supplement whereas another version will portray the patient who feels unchanged after starting a vitamin supplement. The patients will be randomly assigned to participants and otherwise contain identical information. Judgments will be measured by eliciting participants recommendation about continuing the vitamin (Appendix\_Script).

Interventions

OTHERPatient self-report

Simulated patient following structured script

Sponsors

Sunnybrook Health Sciences Centre
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
DOUBLE (Subject, Caregiver)

Eligibility

Sex/Gender
ALL
Healthy volunteers
Yes

Inclusion criteria

* Community pharmacist

Exclusion criteria

* Outside Ontario

Design outcomes

Primary

MeasureTime frameDescription
Response variable in each survey is a binary recommendation whether to continue the vitamin supplement or discontinue the vitamin supplementShort-term (less than 5 minutes)Health provider clinical recommendation

Contacts

Primary ContactDonald A Redelmeier, MD, MSc
dar@ices.on.ca4164806999

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026