Table 4 Examples of claims based on potentially biased evidence
Type | Drug | Claim | Reference | Reasons for potential bias |
|---|---|---|---|---|
Abstract | Pantozol® (Pantoprazol) | Similar healing of reflux disease as omeprazol 20 mg | Bardnan KD et al. Gastroenterology 116(Suppl.4II): A 118, 1999 | Abstract, open study, no blinded outcome assessment |
Selection Bias | Neurodol® (Lidocaine) | Neurodol tissugel reduces pain and allodynia in postherpetic neuralgia | Meier T et al., Pain 106: 151–158, 2003 | Selection bias (only patients who had already successfully been treated with lidocaine for more than 1 month were included in study), very few patients |
Publication bias | Lamictal® (Lamotrigine) | Well tolerated | Bowden CL et al. Drug Safety 2004; 57: 173–184 | Narrative review, possible publication and selective reporting of evidence bias |
At least 3 quality criteria missing | Zoloft® (Sertraline) | Increases cognitive capacity | Newhouse PA et al. J Clin Psych 2000;61:559–68 | High drop out rate(>30%), no descriptions of losses to follow-up, selective reporting of positive outcomes |
Post hoc analysis | Jarsin® (St. John's word) | Similar efficacy as synthetic antidepressants | Brenner R et al. Clinical Therapeutics 22: 411–419, 2000 | Post-hoc analysis, only 15 patients in each group, no sample size calculation |