Alcohol is consumed by an estimated 137.4 million people in the USA 12 years of age and older and, as a result, is estimated to have caused about 140 thousand deaths among people 20 to 64 years of age each year from 2015 up to and including 2019.

The proposed review of the evidence on alcohol’s impact on health aims to produce conclusions to inform the Dietary Guidelines for Americans, 2026–2030. A multi-method approach will be utilised to formulate conclusions on (i) weekly (ie, average) thresholds to minimise long-term and short-term risks of morbidity and mortality, (ii) daily thresholds to minimise the short-term risk of injury or acute illness due to per occasion drinking, (iii) alcohol use among vulnerable populations (eg, pregnant women) and (iv) situations and circumstances that are hazardous for alcohol use. To inform expert decisions, this project will also include a systematic review of existing low-risk drinking guidelines, a systematic review of meta-analyses which examine alcohol’s impact on key attributable disease and mortality outcomes, and of estimates of the lifetime absolute risk of alcohol-attributable mortality and morbidity based on a person’s sex and average level of alcohol use. The systematic reviews were designed in accordance with the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P). The preliminary conclusions produced as a result of this project will undergo public consultation, and data from these consultations will be qualitatively analysed. The results of the public consultations will be used to further revise and refine the project’s conclusions.

The study was granted an ethics exemption as only secondary data sources and unidentifiable public consultation will be utilised. Systematic reviews are pre-registered with PROSPERO (registration numbers CRD42024584924 and CRD42024584948).

This project will establish a scientific consensus concerning alcohol’s impact on health. This consensus is imperative for informing the upcoming Dietary Guidelines for Americans, 2026–2030, and for better informing individuals about the health risks associated with alcohol use.

Perineal trauma is one of the most common complications of childbirth, impacting approximately 9 out of 10 women who undergo a vaginal delivery. Perineal trauma is a public health issue leading to increased maternal morbidity and decreased quality of life. Although race is being studied as a potential risk factor and predictor of perineal trauma, other contributing factors like racism and social determinants of health have not been adequately studied in the same context. We set out to synthesise the available peer-reviewed evidence evaluating the prognostic association between race and perineal trauma.

This systematic review and meta-analysis adheres to the PRISMA-P (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols) and PROGRESS (Prognosis Research Strategy) guidelines and is registered with PROSPERO. The review explores the association between racial status (non-Hispanic white vs non-white) and perineal birth trauma using the PECOTS (Population, Intervention/Exposure, Comparator, Outcome, Timing and Setting) framework. We will search PubMed, CINAHL, Web of Science and Embase. Peer-reviewed observational studies will be included. Data extraction and screening will be done in duplicate. Analyses will use random-effects models in R, reporting both unadjusted and adjusted risk differences. Risk of bias will be assessed using ROBINS-I (Risk of Bias in Non-randomised Studies of Interventions). Heterogeneity and certainty of evidence will be evaluated using I² and GRADE (Grading of Recommendations Assessment, Development and Evaluation), respectively.

This is a systematic review based on previously published data, and therefore ethical approval is not required. The findings of this review will be disseminated through publication in a peer-reviewed journal and presented at academic conferences.

CRD42025590093.