Participants, Study Characteristics, and Frames for Treatment Scenarios

Article	Subjects	Design	Scenario Presented	Frames	Outcomes	Methodological Comment
Positive Versus Negative Framing (surgical treatment)
Gurm 200015	Patients in waiting area of outpatients clinic N = 116	RCT parallel groups	Video presentation describing risks and benefits of angioplasty. Two scenarios: (A) to improve symptoms of chest pain, (B) to reduce the risk of heart attack.	Positive frame—% safe Negative frame—number with complication out of 100	Intention to undergo angioplasty	No control group. Baseline characteristics on age, gender, education, and experience with angioplasty comparable (no data given).
Smith 199633	Psychology students and students approached on campus N = 73	RCT parallel groups	Information presented on surgery vs radiotherapy for a rare cancer. Describes survival during treatment, at 1 year, and at 5 years.	Positive frame—number alive out of 100 people after treatment Negative frame— number dying out of 100 people after treatment	Intention to undergo surgery/ radiotherapy	No control group. No information on how questionnaires were administered. Baseline characteristics on gender reported but not examined by framing group. Results stratified by enjoyment in thinking about persuasive messages (low vs high need for cognition).
Marteau 198922	Medical students participating in psychology course N = 74	RCT parallel groups	Information presented on surgery vs no treatment for terminal liver disease. Subjects responded either as a patient or doctor. Probability of survival varied.	Positive frame—% surviving the operation Negative frame—% dying after operation	Intention to undergo surgery	No control group. 2 × 2 design (role by message frame). Baseline characteristics not reported.
Rybash 198931	Psychology students N = 301	Non-RCT parallel groups	Presents scenario of a male patient deciding whether to consent to surgery for heart disease. Whether patient consents/refuses surgery and age of patient (40 vs 70) manipulated.	Positive frame—% survive surgery, expected to live 10–15 years Negative frame—% die during surgery, expected to die 10–15 years	Intention to undergo surgery	No control group. 2 × 2 × 2 design (framing by patient age by patient choice). Participants tested in group setting. Baseline characteristics not reported.
McNeil 198824	Radiology students N = 390 Medicine and science students N = 402	Non-RCT parallel groups	Information on surgery vs radiation therapy for lung cancer. Describes survival during treatment, at 1 year, and at 5 years.	Positive frame—number alive out of 100 people Negative frame—number dying out of 100 people Mixed frame—number dying and alive out of 100 people	Intention to undergo surgery	Mixed frame control group. Little methodological information given. No information on baseline characteristics.
Wilson 198735	Psychology students participating for course requirement N = 91	RCT parallel groups	Information on surgery vs no treatment for terminal liver disease. Probability of survival after surgery varied.	Positive frame—% surviving the operation Negative frame—% dying after operation	Intention to undergo surgery	No control group. Questions presented in random order. Baseline characteristics on age and gender reported but not examined by framing group.
McNeil 19828	Chronically ill outpatients N = 238 Business school students N = 491 Radiologists N = 424	Non-RCT parallel groups	Information on surgery vs radiotherapy for lung cancer. Describes survival during treatment, at 1 year, and at 5 years. Treatment was either identified (surgery vs radiotherapy) or unidentified (treatment A vs B). Outcomes expressed as cumulative probability and life expectancy.	Positive frame—number alive out of 100 people Negative frame—number dying out of 100 people	Intention to undergo surgery/radiotherapy	No control group. Patients interviewed individually, students and physicians written questionnaire (mode of administration not described). Baseline characteristics on age reported but not examined by framing group.
Positive Versus Negative Framing (medication treatment)
Jasper 200146	Consecutive female “Motherisk” callers seeking information about allergy-related drugs during pregnancy N = 105	RCT parallel groups	Information on teratogenic risk for applicable allergy- related drug information and measures administered over the telephone.	Positive frame—% risk of not giving birth to a child with a birth defect Negative frame—% risk of giving birth to a child with a birth defect	Intention to take allergy medication	No control group. Women alternately allocated to framing groups. Baseline information on age, gravidity, parity, first-time caller, currently pregnant, and exposure to medication comparable.
Farrell 200145	Students responding to class announcements N = 254	RCT parallel groups	Written information on risk of contracting HIV and hepatitis C through a blood transfusion. Presents scenario of requiring a blood transfusion during surgery.	Positive frame—number not infected out of 2 million units transfused Negative frame—number infected out of 2 million units transfused Mixed frame—number infected out of 2 million units transfused, embedded in positive context of safe blood transfusion history	Perceived safety of receiving a blood transfusion	Mixed and negative frame report same numerical data. Completed tasks in group setting (states participants did not see other conditions). Baseline characteristics on age, gender, and donation history comparable. Results stratified by donation history.
Krishnamurthy 200144 Study 1	Students N = 143	RCT parallel groups	Presented two versions with different phrasing: attribute frame—percentage of patients improving; goal frame—chance of improvement. Varied probability of better results from treatment. Participants chose a personal health condition.	Positive frame—% chance of better results Negative frame—% chance treatment fails to provide better results	Intention to see physician about treatment	No control group. 2 × 2 design (frame by phrasing). Baseline characteristics on age and gender reported but not by framing group.
Krishnamurthy 200144 Study 2	Patients attending health clinic N = 117	RCT parallel groups	As above.	Positive frame—% chance of better results Negative frame—% chance fails to provide better results	Intention to see physician about treatment	No control group. 2 × 2 design (frame by phrasing). Baseline characteristics on age and gender reported but not by framing group.
Zimmerman 200036	Consecutive breast cancer patients at oncology outpatient clinic N = 35	Within subjects	Presented information using a modified decision board instrument on adjuvant chemotherapy at 3 different levels of cure/recurrence.	Positive frame—% cure Negative frame—% disease recurrence	Intention to undergo chemotherapy	Fixed order of presentation (positive frame presented 2 months after negative). Baseline characteristics on age, marital status, employment, and clinical characteristics provided.
Bernstein 199911	Psychology students responding to posted notice N = 216	Within subjects	Presented information on 2 supplementary drugs for a chronic disease that either prolonged or shortened life from the 20-year effect of a baseline drug. Effects were described separately for supplementary and baseline drugs (segregated editing) or combined (integrated editing). Expected value (EV) in years of life varied from −5 to +25.	Gain frame— supplementary drug prolongs life Loss frame—supplementary drug shortens life Mixed frame—either prolongs or shortens life	Intention to take supplementary drug	Between-subjects design for editing type, within-subjects design for framing condition —order randomized. No order effects found. Baseline characteristics on gender and age reported.
Blumenschein 199843	Pharmacy studentsN = 182	RCT parallel groups	Presented written information on treatment for arthritis. Received information described as time trade-off (years) and standard gamble (percent).	Positive frame—years in full health, % chance of success Negative frame—years willing to give up for full health, % chance of failure	Intention to undergo treatment	No control group. Completed tasks in group setting. Baseline characteristics not reported.
Bier 199412	Psychology students participating for course requirement N = 140 (study 1) N = 256 (study 2)	Non-RCT parallel groups	Information on effectiveness and side effects of 2 treatments for various conditions (e.g., cholesterol lowering). One treatment described as ambiguous with conflicting results from 2 studies reported.	Positive frame—% experiencing no side effects from treatment Negative frame—% experiencing side effects from treatment	Intention to undergo treatment	No control group. 2 × 2 × 2 design (framing by ambiguity by probability order). Baseline characteristics on age and gender reported but not examined by framing group. Results stratified by level of optimism (LOT).
Jacoby 199317	Consecutive epilepsy patients eligible for medication withdrawal N = 72	RCT parallel groups	Written information on seizure recurrence after medication withdrawal provided to patients.	Positive frame—likelihood of remaining seizure free Negative frame— risk of seizure recurrence	Actual treatment choice	No control group. Patients alternately allocated to framing groups. Baseline characteristics not reported.
Levin 198819	Psychology students N = 160	Non-RCT parallel groups	Information on a hypothetical medical treatment for cancer.	Positive frame—% success rate Negative frame—% failure rate	Perceived treatment effectiveness	No control group. Baseline characteristics for gender comparable.
O'Connor 198926	Consecutive outpatients from cancer clinic N = 154. Healthy volunteers of university staff, students, and their neighbors N = 129	RCT parallel groups	Information presented on 2 hypothetical treatments for cancer. Only treatment A had side effects. Probability of survival for treatment B varied.	Positive frame—% survival after 1 year Negative frame—% dying after 1 year Mixed frame—both % survival and % dying after 1 year given	Intention to undergo treatment	Mixed-frame control group. Order of probability level randomized (ascending or descending). No order effects in mixed frame group. Baseline characteristics on age, gender, health professionals, and therapy reported but not examined by framing group.
O'Connor 198525	Nursing students N = 216 Visitors to an open house at Ontario Cancer Institute N = 208	RCT parallel groups	Describes 2 treatments for cancer (IV versus tablet). IV treatment has higher chance of side effects. Probability of survival varied for treatment in tablet form.	Positive frame—% survival after 1 year Negative frame—% dying after 1 year Mixed frame—% survival then dying after 1 year given Mixed frame—% dying then survival after 1 year given	Intention to undergo treatment	Mixed-frame control group. Visitors self-selected to medium of questionnaire administration (computer vs pen/paper). No order effects in mixed-frame group. Baseline characteristics on age, gender, professional status, and class (students) reported but not examined by framing group.
RRR Versus ARR or NNT (medication treatment)
Straus 200242	Consecutive patients with NVAF N = 17	Within subjects	Information presented on warfarin medication for stroke	Same information framed as RRR/RRI,ARR/ARI,NNT/NNH,LHH	Intention to take medication	Order of presentation randomized. Baseline characteristics on age, gender, and previous stroke provided.
Misselbrook 200141	Hypertensive patients N = 102. Matched non- hypertensive patients N = 207	Within subjects	Information presented on advantages and disadvantages of treating mild hypertension (labeled as stroke prediction factor). Data obtained from MRC Mild Hypertension Trial.	Same information framed as RRR, ARR, NNT, personal probability	Intention to take medication	Participants unaware of hypertension focus of study. Baseline characteristics on age, gender, housing tenure, and familiarity with stroke provided.
Hux 199516	Outpatients from family practice, hypertension, and cardiology clinics N = 100	Within subjects	Presented information on a cholesterol-lowering drug used to reduce CAD. Data obtained from Helsinki Heart Study. Two scenarios on hypertension medication inserted to reduce respondents discerning that a single medication was being described.	Same information framed as RRR, ARR, NNT, average and stratified gain in disease-free survival	Intention to take medication	All received same information. Questions appeared in random order—not varied between questionnaires. Baseline characteristics on gender, age, history of heart disease, attending cardiology clinic, and taking cardiovascular medication provided.
Malenka 199321	Consecutive outpatients from general internal medicine practice N = 470	Within subjects	Information on 2 medications for a life-threatening disease. Both medications were equivalent in costs, side effects, and effectiveness. Underlying risk of death and treatment benefit varied (10% or 80% for both).	Medication A—framed as RRR Medication B—framed as NNT	Intention to take medication	Within-subjects design for framing, between-subjects for underlying risk of death and treatment benefit. Baseline characteristics on age, gender, education, medical history, and overall health reported.
Probability Versus Frequency (medication treatment)
Siegrist 199732	Psychology students N = 105	Non-RCT parallel groups	Presented information on hypothetical new medication for a serious illness. Risk of dying varied (high vs low).	Probability frame—probability of dying after treatment Frequency frame—number dying out of 1 million after treatment	Willingness to pay for treatment	No control group. 2 × 2 design (framing by level of risk). Completed questionnaires in groups. Baseline characteristics on age and gender reported but not examined by framing group.

RCT, randomized controlled trial; non-RCT, nonrandomized controlled trial; within-subjects, participants received all frames; RRR, relative risk reduction; RRI, relative risk increase; ARR, absolute risk reduction; ARI, absolute risk increase; NNT, number needed to treat; NNH, number needed to harm; LHH, likelihood of being helped or harmed; CAD, coronary artery disease; IV, intravenous; HIV, human immunodeficiency virus; NVAF, nonvalvular atrial fibrillation.