Causal inference from longitudinal studies with baseline randomization.
We describe analytic approaches for study designs that, like large simple trials, can be better characterized as longitudinal studies with baseline randomization than as either a pure randomized experiment or a purely observational study. We (i) discuss the intention-to-treat effect as an effect measure for randomized studies, (ii) provide a formal definition of causal effect for longitudinal studies, (iii) describe several methods -- based on inverse probability weighting and g-estimation -- to estimate such effect, (iv) present an application of these methods to a naturalistic trial of antipsychotics on symptom severity of schizophrenia, and (v) discuss the relative advantages and disadvantages of each method.
Sengwee
S
Toh
Miguel A
MA
Hernán
D014150:Antipsychotic Agents / Q000627:therapeutic use; D056808:Biostatistics / Q000379:methods*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies / Q000706:statistics & numerical data*; D008297:Male; D015233:Models, Statistical; D010349:Patient Compliance / Q000706:statistics & numerical data; D011336:Probability; D011897:Random Allocation; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000188:drug therapy; D016896:Treatment Outcome
D014150:Antipsychotic Agents