Assessing general side effects in clinical trials: reference data from the general population

Pharmacoepidemiol Drug Saf. 2011 Apr;20(4):405-15. doi: 10.1002/pds.2067. Epub 2010 Nov 8.


Purpose: Side effects in clinical trials are frequently assessed in an unstructured fashion, using ascertainment strategies with unclear quality criteria. To improve the assessment and interpretation of general side effects, a structured approach is presented and validated (General Assessment of Side Effects, GASE). Base rates and reference data of the general population as well as quality criteria of this new side effect ascertainment method are provided.

Methods: We developed a screener assessing the most common subjective side effects of clinical trials (according to FDA statistics and others). The screener was evaluated in a general population survey including 2512 participants, 1276 of them taking drugs.

Results: We present reference data of the general population that help to interpret and compare future results of clinical trials assessing general side effects. Highest scores for side effects were reported from users of psychopharmacological drugs, medium scores of people taking antihypertensives, and lower scores of people taking lipid-lowering drugs, pain killers, and antidiabetics. If people take multiple drugs, more side effects are reported compared to single-class drugs. This confirms GASE's validity to assess side effects.

Conclusion: We suggest that a structured, patient-based approach to assess general side effects could improve the detection of drug-induced side effects. The problem of clinical studies being underpowered to detect side effects could be reduced by using more reliable approaches. Our plea is for side effect ascertainment with sophisticated approaches for expected side effects, systematic screening for general side effects, and open question methods for spontaneous reports.

Publication types

  • Validation Study

MeSH terms

  • Adult
  • Aged
  • Clinical Trials as Topic / methods*
  • Drug-Related Side Effects and Adverse Reactions*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Quality Indicators, Health Care*
  • Reproducibility of Results