Public health and healthcare

Second plague pandemic

Second plague pandemic: Yersinia pestis epidemics from the Black Death (1346–1353), which killed 30–60% of Europeans, through recurrent waves including the pestis secunda until the early 19th century; originated in the Tian Shan, Central Asia.

Second Xiangya Hospital of Central South University

Second Xiangya Hospital of Central South University (中南大学湘雅二医院), founded 1958 in Changsha, a Triple-A tertiary teaching hospital with 3,500 beds; hosts China's National Medical Center for Mental Disorder and leads in psychiatry and endocrinology.

Secondary Immunization

Secondary immunization, or booster dosing, gives vaccine doses after a completed primary series to restore waning immunity or convert first-dose non-responders; CDC and WHO schedule boosters for tetanus, diphtheria, Hib, MMR, and COVID-19.

Secondary Prevention

Secondary prevention is the level of preventive medicine, defined by Leavell and Clark in 1958, that detects and treats disease early through screening tests like mammography and the Pap smear.

SECRETO study

SECRETO (NCT01934725) is an international case-control study of cryptogenic ischemic stroke in adults 18-49, recruiting 2013-2022 at 19 European centres, studying triggers, cardiac, thrombotic, and genetic causes with 10-year follow-up.

Seema Verma

Seema Verma is an American health policy executive who led the Centers for Medicare & Medicaid Services from 2017 to 2021 under President Trump, later joining Oracle Health.

Segregation analysis

Segregation analysis is a statistical genetics method that tests whether a trait's transmission through families fits Mendelian inheritance at a single locus, estimating parameters such as transmission probabilities and penetrance.

SEIR model

The SEIR model, or SEIR epidemic model, is an epidemiological model dividing a population into susceptible, exposed, infectious, and recovered classes to simulate disease spread.

Self-controlled case series

The self-controlled case series is an epidemiological method comparing event rates before and after transient exposures like vaccination, using only cases, introduced by C. P. Farrington in 1995.

Senior Centers

Senior centers are community facilities where older adults gather for congregate meals, wellness activities, and social connection, largely under the US Older Americans Act; about 1 million older adults are connected to services through them.

SENSE trial

SENSE trial (NCT03316547): a randomized trial of 70 preterm infants at St. Louis Children's Hospital testing the Supporting and Enhancing NICU Sensory Experiences program, a parent-delivered daily sensory intervention, versus standard NICU care.

Sequential multiple assignment randomized trial

A sequential multiple assignment randomized trial (SMART) is a multi-stage randomized trial that compares adaptive treatment strategies, re-randomizing participants at later decision points based on their response to earlier treatment.

Seroprevalence survey

A seroprevalence survey is an epidemiological study measuring the proportion of a population with antibodies against a pathogen, capturing infections missed by case reporting; influenza antibody surveys date to the 1930s.

Services Hospital

Services Hospital, Lahore (SHL) is a government teaching hospital on Jail Road, Lahore, Pakistan, founded 1958 as a Mayo Hospital outpatient department. Now the 1,600-bed teaching hospital of SIMS, with a 2023 upgrade adding 24 operation theatres.

Severance Hospital

Severance Hospital (세브란스병원), Yonsei University's teaching hospital in Seoul, descends from Gwanghyewon/Chejungwon, Korea's first Western-style hospital, founded 1885 by Dr. H.N. Allen and renamed after donor Louis H. Severance in 1904.

Sex Distribution

Sex distribution is the composition of a population by sex, also a MeSH descriptor (D017678). Covers sex ratios by age, skewed birth ratios, missing female births, and female underrepresentation in clinical studies.

SEXCHECK study

SEXCHECK (NCT06458764) is a cross-sectional observational study at Candiolo Cancer Institute, Torino, measuring sexual dysfunction incidence and related distress in premenopausal breast cancer survivors on endocrine therapy, enrolling about 150 women aged 18-55.

Seymour Perry

Seymour Perry (died 2000) was an American physician and pioneer of health technology assessment, first director of the National Center for Health Care Technology and founder of ISTAHC.

Shanghai Children's Medical Center

Shanghai Children's Medical Center (上海儿童医学中心), a tertiary A-level children's hospital in Pudong, Shanghai, co-founded with Project HOPE, opened 1998, National Children's Medical Center since 2017, Zhangjiang campus 2024.

Shared medical appointments

A shared medical appointment, also called a group medical visit, is a clinical encounter where patients with a similar condition are seen together by a clinician team.

Sheila A. Ryan

Sheila A. Ryan is an American nurse scholar and emeritus professor at the University of Nebraska Medical Center who served as dean at Creighton University and the University of Rochester.

Sheldon Greenfield

Sheldon Greenfield (died 2025) was an American general internist and health services researcher at UC Irvine who co-led the Medical Outcomes Study and was elected to the National Academy of Medicine in 1996.

Sherri Tenpenny

Sherri Jane Tenpenny, Ohio osteopathic physician and anti-vaccine activist, author of Saying No to Vaccines, Disinformation Dozen member, known for 2021 magnetism testimony and 2023 license suspension.

SHINE trial (NCT01824940)

The SHINE trial (Sanitation Hygiene Infant Nutrition Efficacy) was a cluster-randomized trial in rural Zimbabwe testing whether water, sanitation, hygiene, and infant feeding interventions improved child growth.

Shmuel Penchas

Shmuel Penchas is a Jerusalem physician who ran the Hadassah Medical Organization for eighteen years and argued that health care reform may be logically impossible.

Shoulder study

Shoulder study: NCT06909864, a 2019-2021 Hacettepe University cross-sectional study of 48 Turkish adolescent competitive swimmers versus 28 controls, finding sport-specific but not stroke-specific shoulder adaptations, published in Physical Therapy in Sport 2025.

Shriners Hospitals for Children

Shriners Hospitals for Children, also branded Shriners Children's, is a 501(c)(3) pediatric specialty healthcare system founded in 1922 in Shreveport, Louisiana, owned by the Shriners International Masonic fraternity, treating children regardless of ability to pay.

sICAM-1 study

sICAM-1 studies measure soluble intercellular adhesion molecule-1, an endothelial activation marker, in obese children and adolescents; levels are higher than in healthy controls, correlate with carotid IMT and insulin resistance, and respond inconsistently to exercise.

sifap1 study

The sifap1 study (Stroke in Young Fabry Patients) was a European observational cohort study of 5,023 stroke patients aged 18 to 55 that found definite Fabry disease in 0.5%.