A natural experiment is a causal inference study design grounded in real-world research. Its core concept is to use quasi-random variation in exposure generated by external factors to evaluate the effects of interventions or exposures on outcomes. It is particularly suitable for research settings in which randomized controlled trials （RCTs） are infeasible or ethically constrained， and it combines causal inference capacity with relatively strong external validity. This article provides an overview of the definition， key features， and current application status of natural experiments， and proposes the application scenarios for applying natural experiment strategies to the evaluation of therapeutic effects in traditional Chinese medicine （TCM）， including policy implementation or policy change evaluation， assessment of variations in clinical practice within hospitals， and evaluation of differences in resource allocation across regions or institutions. The design pathway includes starting from clinical or policy-related TCM questions， systematically collecting relevant data， performing statistical modeling and effect estimation， and interpreting effect estimates in the context of clinical practice. It further analyzes the advantages and challenges of using natural experiments in TCM.

A natural experiment is a causal inference study design grounded in real-world research. Its core concept is to use quasi-random variation in exposure generated by external factors to evaluate the effects of interventions or exposures on outcomes. It is particularly suitable for research settings in which randomized controlled trials （RCTs） are infeasible or ethically constrained， and it combines causal inference capacity with relatively strong external validity. This article provides an overview of the definition， key features， and current application status of natural experiments， and proposes the application scenarios for applying natural experiment strategies to the evaluation of therapeutic effects in traditional Chinese medicine （TCM）， including policy implementation or policy change evaluation， assessment of variations in clinical practice within hospitals， and evaluation of differences in resource allocation across regions or institutions. The design pathway includes starting from clinical or policy-related TCM questions， systematically collecting relevant data， performing statistical modeling and effect estimation， and interpreting effect estimates in the context of clinical practice. It further analyzes the advantages and challenges of using natural experiments in TCM.

OBJECTIVE:To compare the efficacy and safety of Jinkui shenqi pill versus Shengjing capsule in the treatment of oligoasthenozoosperimia under behavioral intervention. METHODS:98 patients with oligoasthenozoosperimia were randomly divid-ed into Shengjing capsule group(49 cases)and Jinkui shenqi pill(49 cases). All patients received intervention treatment(cognitive intervention,psychological intervention,diet intervention and exercise intervention,etc.). Based on it,Shengjing capsule group re-ceived 1.6 g Shengjing capsules,orally,3 times a day;Jinkui shenqi pill group received 6 g Jinkui shenqi pill,orally,twice a day. They were treated for 3 months. Clinical efficacy,semen quality (semen volume,sperm concentration,sperm motility rate, sperm motility)and sex hormone levels [testosterone(T),follicle stimulating hormone(FSH),luteinizing hormone(HLH),pro-gesterone(P),prolactin(PRL)] before and after treatment,and the incidence of adverse reactions in 2 groups were observed. RE-SULTS:The total effective rate in Shengjing capsule group was significantly higher than Jinkui shenqi pill group,with statistical significance(P<0.05). Before treatment,there were no significant differences in semen quality and sex hormone levels(P>0.05). After treatment,semen quality in 2 groups was significantly higher than before,semen volume and sperm motility in Shengjing cap-sule group were higher than Jinkui shenqi pill group,with statistical significances(P<0.05). T levels in 2 groups were significant-ly higher than before,while Shengjing capsule group was lower than Jinkui shenqi pill group,with statistical significances (P<0.05);and there were no significant differences in FSH,HLH,P and PRL before and after treatment in 2 groups(P>0.05). And there was no significant difference in the incidence of adverse reactions(P>0.05). CONCLUSIONS:Under behavioral interven-tion,Shengjing capsule has better efficacy than Jinkui shenqi pill in the treatment of oligoasthenozoosperimia,it can significantly improve semen quality,while Jinkui shenqi pill is better in terms of improving sex hormone levels;and both show good safety.