Table 6. Characteristics of included studies (by study design, year of publication, then sample size).
Study Design | Study (First Author Name) | Study Site, Year | Participants (n) | Medication | Intervention/Exposure | Outcome Measure(s) |
RCT | Freemantle [35] a | UK 2000 | PCPs (79: 40 intervention, 39 control) | Lansoprazole versus omeprazole | PSR visits: PSRs instructed by local health authority (one visit); controls: normal detailing | Switch from omeprazole to less costly lansoprazole |
Dolovich [36] a | Canada 1999 | PCPs and pediatric specialists (641 in intervention group and 574 in control group) | Antibiotics for otitis media | PSR visits, PSRs trained in evidence-based education by academic department of a university; Control group: no detailing | Market share of antibiotics for otitis media | |
Controlled cohort studies | Andersen [37] b | Denmark 1999–2003 | 297 PCPs (26 intevention/271 controls) | Asthma medications | Participation in a RCT funded by a pharmaceutical company | Prescribing trial drug; Adherence to prescribing guidelines |
Case-control Studies | Spingarn [39] | US° 1990 | Hospital residents (75) | Medications for Lyme disease | Intervention: presentation by academic who was also a pharmaceutical executive; Controls: did not attend | Appropriateness of intention to prescribe for mild versus severe Lyme disease |
Chren [38] | US 1989–1990 | Physicians (40 cases, 80 controls) | Addition to hospital formulary | PSR visits; cases added to formulary, controls did not | Addition of detailed drug to hospital formulary | |
Time series analyses (econometric) | Ching [78] c | Canada 1993–1999 | Physician's prescribing antihypertensives in Canada | Antihypertensive medications (angiotensin converting enzyme inhibitors and diuretics) | PSR visits (n minutes) | Market share; Elasticity of demand |
Venkataraman [40] b | Not stated 2002–2003 | Physicians (2,774) | Statins, coagulation drugs, erectile dysfunction drugs, gastrointestinal drugs, placebo | PSR visits (total number); attendance at pharmaceutical; sponsored meetings; (total number attended) | n prescriptions | |
Windmeijer [41] c | Netherlands 1995–1999 | PCPs and psychiatristsd | 11 therapeutic markets (over 50% of the Dutch drug market) | PSR visits (expenditure); Journal advertisements (expenditure); Mail (expenditure) | n prescriptions; Cost of prescriptions | |
Chintagunta [42] c | US, UK, Germany, France, Italy 1989–1999 | Prescribers of antidepressant medications | Fluoxetine, sertraline, paroxetine | PSR visits (expenditure) | Market share (sales) | |
Narayanan [43] e | US 1993–2001 | All prescribers of antihistamines in USd | 2nd generation antihistamines: loratidine cetirizine, fexofenadine | PSR visits (total expenditure) | New prescriptions per month | |
Donohue [44] c | US 1997–2000 | 11,000 office and hospital physicians | First prescriptions of 6 antidepressants | Monthly spending on PSR detailing | New prescriptions | |
Mizik [45] b | US 2004 | Physicians (74,075) | 3 unknown drugs | PSR visits | n new prescriptions for the three study drugs | |
Manchanda [46] b | US 1999–2001 | Physicians (1,000), 18.5% specialists (for study drug), 60.1% PCPs, 21.4% other specialists, controls (1,000) | Drug unknown | PSR visits | Numbers of prescriptions | |
Manchanda and Chintagunta [47] b | US 1996–1998 | Physicians (1,000), 11% specialists (for study drug), 59% PCPs, 30% other specialists | Drug unknown | PSR visits | n prescriptions; Prescriptions of specialists versus primary care physicians versus other specialists; Prescriptions by male and female physicians | |
Berndt [48] c | US 1977–1993 | All US physicians | H2 antagonist antiulcer drugs (cimetidine, ranitidine, famotidine, nizatidine) | PSR visits (min) | Sales volume (units of average daily dose) and market share; Elasticity of demand | |
Rosenthal [79] c | US 1996–1999 | Large sample of office and hospital physiciansd | Medications prescribed in primary care | PSR visits (expenditure) | Sales of detailed medications per month | |
Azoulay [49] c | US 1977–1993 | All prescribing physicians | H2 antagonist antiulcer drugs (cimetidine, ranitidine, famotidine, nizatidine) | PSR visits; Journal advertisements | Market share for the four H2 antagonists (patient days of therapy) | |
Gonul [69] c | US 1989–1994 | Physiciansd | One medication for a particular indication “relatively more common among the elderly” | PSR visits (min) | n prescriptions; Cost of Prescriptions | |
Rizzo [50] c | US 1988–1993 | All prescribers of antihypertensives in the USd | Antihypertensive medications | PSR visits (expenditure) | Sales of detailed medication; Price elasticity; Quadratic term for sales | |
Hurwitz [51] c | US 1978–1983 | Specialists and PCPs prescribing promoted drugsd | Brand and generic drugs | Total promotional investment in PSR visits, journal advertising, direct mail advertising | Market share held by original brand; Market share held by generic competitors (measured in n pills sold) | |
Mackowiak [52] c | US 1977–1981 | Office based physicians across the USd | Benzodiazepines for anxiety; Diuretics for hypertension | PSR visits (expenditure); Journal advertisements (expenditure) | Expenditure on prescriptions; Market size and market share | |
Leffler [53] c | US 1968–1977 | Not statedd | 51 new products | Total promotional outlay (PSR visits, journal advertising) | Market share 2 y after market entry; Market share in 1977 for drugs introduced since 1968 expressed | |
Telser [54] c | US 1963–1972 | All prescribing physiciansd | Prescription medications in: the hospital market and drugstore market | Promotional intensity: ratio of total promotional outlays/total sales (includes PSR visits, journal advertising, direct mail) | Proportion of sales for entrant drugs | |
Time series analyses (other) | Spurling [55] | Australia 2004–2005 | PCPs (7) | Medications prescribed in primary care | PSR visits; Promotional items in PCP surgeries | Generic prescribing (% of total) |
Stafford [56] c | US 1996–2002 | Physicians (3,500) | Alpha-blockers | PSR visits (expenditure) | Prescriptions | |
Charbit [34] | France 1991–2001 | Prescribing physicians in Franced | 6 classes of antihypertensive medications | Journal advertising (n pages) | Drug sales for each of the six classes of antihypertensive medications | |
Auvray [57] e | France 1992–1998 | PCPs, ear nose throat surgeons, chest physicians, psychiatrists-1,600 | Macrolide antibiotics and psychoanaleptic antidepressants | Total promotional investment | n prescriptions | |
Cleary [26] | US 1988 | Physicians prescribing 3rd generation cephalosporinsd | Ceftazidime, cefriaxone, cefotaxime | PSR visits | New prescriptions; n doses | |
Soumerai [58] e | US 1974–1983 | All propoxyphene prescribers in USAd | Propoxyphene | PSR visits (to warn about risks of propoxyphene) | Sales of propoxyphene; No-refill rates of prescriptions | |
Before–after Studies | Hemminki [25] e | Estonia 2000 | Gynecologists and PCPs (342) | Hormone replacement therapy | Journal advertisements; Pharmaceutical company-sponsored medical education | Probability of detailed drug being prescribed |
Schwartz [27] | US 1999–2000 | Psychiatry residentsd | Psychiatric medications | PSR detailing (12 wk period when residents were detailed versus 12 wk with no detailing) | New prescriptions | |
Kazmierczak [59] | US 1996 | Physicians (60) | Tramadol | Drug company letter to physicians warning about tramadol seizure risk | Prescriptions for tramadol in high risk patients | |
Orlowski [28] | US 1992 | Hospital physicians (20) | Intravenous hospital medications called A (antibiotic) and B (cardiovascular drug) | Attendance at pharmaceutical sponsored meetings (all expenses paid trips to vacation site) | n prescriptions before and after the sponsored meetings | |
Bowman [60] | US date not stated | Physicians (374) | Calcium channel blockers and beta-blockers | PSR sponsored continuing medical education course | Self-reported new prescriptions | |
Cross-sectional studies | Henderson [29] | Australia 2003–2005 | PCPs (1,336) | 7 advertised pharmaceutical products | Advertising on clinical software | n prescriptions |
Kreyenbuhl [31] | US 2003–2004 | Psychiatristsd | Antipsychotic medication | PSR visits; Attendance at pharmaceutical sponsored meetings | Use of “switch” or “add” strategies in treatment of refractory schizophrenia | |
de Bakker [61] | Netherlands 2001 | PCPs (138) | Medications prescribed in primary care | PSR visits; Reliance on commercial sources of information | n prescriptions | |
Steinman [62] | US 1995–1990 | Physicians (97) | Gabapentin | PSR visits | Intention to prescribe gabapentin | |
Greving [30] | Netherlands 2003 | PCPs (70) | Angiotensin II receptor blockers | PSR visits; Journal advertisements; Attendance at pharmaceutical sponsored meetings | New prescriptions of this drug | |
Canli [32] | Turkey 2001 | PCPs (316) | Antibiotics for acute tonsillopharyngitis | PSR visits | Intention to prescribe antibiotics | |
Verdoux [63] | France 2004 | PCPs (848) | Antipsychotic medication | PSR visits | Initiation of antipsychotic medication in a 1-mo period | |
Muijrers [64] | Netherlands 2000–2001 | PCPs (1,434) | Medications prescribed in primary care | PSR visits | Quality of prescribing (determined by panel of experts) | |
Huang [65] | US 2001–2003 | Resident physiciansd | Antidepressants | Sponsorship of resident conferences | Prescription of antidepressants from sponsoring companies | |
Watkins [66] | UK 1995–1996 | PCPs (1,714) | Medications prescribed in primary care | PSR visits (at least once per week); Journal advertisements; Reading written material from pharmaceutical companies | Cost of prescriptions | |
Prosser [67] | UK 1999–2000 | PCPs (107) | New medications prescribed in primary care | PSR visits; Journal advertisements/mailings (considered together) | New drug prescriptions (high/medium/low prescribers) | |
Caamano [68] e | Spain 1993 | Physicians (234) | All prescribing | PSR visits | n prescriptions ; Cost of prescriptions | |
Mansfield [82] | Australia 1999 | PCPs (1,174) | Medications used in primary care | PSR visits (self-report); Attendance at pharmaceutical sponsored meetings (self-report) | Quality use of medicine score | |
Jones [70] | UK 1995–1997 | PCPsd | Nine new drugs | Journal advertisements | Prescribing data for the advertised drugs | |
Caudill [71] | US 1996 | PCPs (446) | Medications for acute bronchitis, hypertension and urinary tract infection | PSR visits (frequency of use) | Cost of prescribing | |
Berings [72] | Belgium date not stated | PCPs (128) | Benzodiazepines | PSR visits (n visits in last 4 wk) | Prescription of benzodiazepines | |
Lurie [73] | US 1987–1988 | Hospital physicians (240 faculty staff and 131 residents) | Hospital medications | PSR visits (<5 min and >5 min) | Change in prescribing habit Addition to hospital formulary | |
Healthcare Communications [80] | US 1987–1988 | Physicians (1184) | Newly promoted medications | Journal advertisements (awareness of) | Market share | |
Peay [33] | Australia 1981 | PCPs (74) and specialists (50) | Temazepam | PSR visits (contact versus no contact); Direct mailing; Attendance at PSR-sponsored function | Temazepam prescription | |
Blondeel [81] | Belgium 1987 | PCPs (358) | Medications prescribed by PCPs | PSR visits | Response to 8 simulated patients where prescribing was not advisable. Quality index compiled based on GP medication choices by expert panel (range 1–100) Proneness to prescribe (proxy for prescribing frequency) | |
Haayer [74] | Netherlands 1979 | PCPs (116) | Medications that would result from 8 case-histories devised by a panel | PSR visits; Journal advertisements; Companies' mailings | Prescribing rationality based on a composite scale (drug choice, duration, dose and use of combination products) | |
Walton [75] | US 1976–77 | PCPs (29%) and specialists (71%) (1,000 total) | 186 different medications | Journal advertisements | Prescriptions of advertised drugs (intention to prescribe) | |
Dajda [76] | UK 1975 | PCPs in UKd | Branded advertised drugs in the UK | Mailed advertisements (number in 1 y) | n prescriptions | |
Becker [77] | US 1970 | PCPs (29), internists (3). osteopathic physicians (5) | Chloramphenicol, equagesic, vitamin B12, methylphenidate, oral contraceptives | Use of journal advertisements PSR visits (frequency) | Proportion of chloramphenicol scripts. Physicians' self-reported prescribing behaviour. |
Experimental partnerships between pharmaceutical company and health authority or academic department.
Data from pharmaceutical company.
Information from a market research company.
Total number unknown.
Using national prescribing data.
PCP, primary care provider; RCT, randomized controlled trial.