Table 1.

Strengths and limitations of using routinely collected health data to examine long-term effects of medication use during pregnancy.

Strengths	Limitations
Can answer a variety of research questions in a relatively timely and efficient manner	Restricted to investigating exposure and outcomes routinely recorded in the data
Commonly population-based, improving generalizability of findings and reducing potential for selection bias	Potential misclassification of medication exposures and outcomes
Datasets often contain data on many individuals and can therefore generate large sample sizes	Assumptions regarding dose, timing, and duration of medication exposure based on dispensing data
Data routinely collected as part of clinical practice/administration requirements	Diagnostic data often not available (i.e. severity of underlying illness)
Unobtrusive data collection	Available data limited to that which is routinely collected. Relevant data of interest (i.e. potential confounders) not collected
Eliminates potential for recall bias	Data may differ across data sources (i.e. differences in the way data are collected in different settings or changes to data collection over time)
Enables long-term follow-up	Data quality and integrity may differ across data sources
Useful in assessing rare, long-term outcomes	Large sample size can lead to increased likelihood of chance findings