方法对比

	自然实验	单盲随机对照试验
领域	实验设计	实验设计
方法族	Process / pipeline	Process / pipeline
起源年份	1990s (formal methodological articulation); earlier in epidemiology (John Snow, 1854)	1948 (formalized); single-blind variant established in mid-20th century clinical trial methodology
提出者	Varied; systematized in econometrics and political science (e.g., Meyer 1995; Angrist & Krueger 1991)	Bradford Hill and colleagues (MRC streptomycin trial, 1948); blinding conventions codified in CONSORT guidelines
类型	Quasi-experimental research design	Experimental design — blinded randomized trial
开创性文献	Meyer, B. D. (1995). Natural and quasi-experiments in economics. Journal of Business and Economic Statistics, 13(2), 151–161.	Schulz, K. F., Altman, D. G., Moher, D., & CONSORT Group. (2010). CONSORT 2010 statement: Updated guidelines for reporting parallel group randomised trials. BMJ, 340, c332.
别名	natural quasi-experiment, naturally occurring experiment, exogenous shock design, as-if randomization	single-masked RCT, single-blind RCT, single-blind trial, SB-RCT
相关	3	5
摘要	A natural experiment exploits a real-world event, policy, or circumstance that assigns individuals to treatment and control conditions in a way that is plausibly random — or at least exogenous to the outcome of interest. Because the researcher does not control assignment, it occupies a middle ground between a true randomized controlled trial and purely observational research, offering stronger causal leverage than conventional observational designs when the as-if randomization assumption holds.	A single-blind randomized controlled trial (SB-RCT) is a rigorous experimental design in which participants are randomly assigned to treatment or control conditions while remaining unaware of which condition they have received. Investigators, outcome assessors, and data analysts are not blinded. By masking participants, the design eliminates placebo and nocebo response biases on the participant side, while preserving investigator flexibility to administer and monitor the intervention.