Thirty six studies of industry payments and prescribing: thirty positive in every analysis, six mixed, none null
"Most studies (n = 30) identified a positive association between payments and prescribing in all analyses; the remainder (n = 6) had a mix of positive and null findings. No study had only null findings."
Reasonable evidence with real limitations. how we score evidence
Caveat on this rating: A systematic review of observational studies; the authors rate 21 of 36 included studies at serious risk of bias and note possible publication bias. Association across studies of many specialties and drug classes, not psychiatry specifically. The causal language is the authors' inference from timing and dose response, not a trial result.
The payment file tells you who was paid. This review asks the question the file cannot: does the money track what gets prescribed.
Significant findings
Mitchell and colleagues (Annals of Internal Medicine, 2021) searched MEDLINE, Embase, the Cochrane Library, Web of Science and EconLit to 16 September 2020 for studies "that estimated the association between receipt of industry payments (exposure) and prescribing (outcome)." "Thirty-six studies comprising 101 analyses were included."
"Most studies (n = 30) identified a positive association between payments and prescribing in all analyses; the remainder (n = 6) had a mix of positive and null findings. No study had only null findings. Of 101 individual analyses, 89 identified a positive association."
"Payments were associated with increased prescribing of the paying company's drug, increased prescribing costs, and increased prescribing of branded drugs. Nine studies assessed and found evidence of a temporal association; 25 assessed and found evidence of a dose-response relationship."
The authors' conclusion: "The association between industry payments and physician prescribing was consistent across all studies that have evaluated this association. Findings regarding a temporal association and dose-response suggest a causal relationship."
Worth asking
The limits are the authors' own: "The design was observational, 21 of 36 studies had serious ROB, and publication bias was possible." Observational studies cannot prove that a payment caused a prescription, and doctors who already favour a drug may be the ones companies choose to pay. What the review rules out is the null: across every study that has looked, none found no association. Put beside the 2024 psychiatry file in this wave, the money is concentrated on a few dozen people and attached to a dozen branded drugs, and the literature says that pattern tends to show up in prescriptions.
Source
Are Financial Payments From the Pharmaceutical Industry Associated With Physician Prescribing? A Systematic Review — Mitchell AP, Trivedi NU, Gennarelli RL, Chimonas S, Tabatabai SM, Goldberg J, Diaz LA, Korenstein D (2021)
Top-tier peer-reviewed journal
Read the source: https://doi.org/10.7326/M20-5665
DOI: 10.7326/M20-5665
How this was scored
- Study design
- Systematic review of observational studies
- Funding
- Independently funded
- Published in
- Top-tier peer-reviewed journal
- Sample size
- not recorded
- Preregistered
- not recorded
- Conflicts disclosed
- not recorded
- Independent of proponent
- not recorded
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published September 21, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "moderate evidence". Reasonable evidence with real limitations. It scores 67 out of 100 on our published rubric. One caveat travels with that badge: A systematic review of observational studies; the authors rate 21 of 36 included studies at serious risk of bias and note possible publication bias. Association across studies of many specialties and drug classes, not psychiatry specifically. The causal language is the authors' inference from timing and dose response, not a trial result. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Are Financial Payments From the Pharmaceutical Industry Associated With Physician Prescribing? A Systematic Review — Mitchell AP, Trivedi NU, Gennarelli RL, Chimonas S, Tabatabai SM, Goldberg J, Diaz LA, Korenstein D (2021). Published in: Top-tier peer-reviewed journal. DOI: 10.7326/M20-5665. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Systematic review of observational studies. Funding: Independently funded. Independence from the proponent is not recorded. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.