The initial search of databases produced 766 results, including a grey literature search in Google or Google Scholar (n = 75). 249 of the results were duplicates. After screening, we selected 19 papers that met the inclusion criteria. The included papers were published between 1993 and 2020. Of the 19, two papers involved solely the use of phone calls to perform SP studies [13, 14]. Only one paper used both methods: simulated patients to visit the medical centres in person and to make phone calls [15]. Both the studies involving solely phone calls had their simulated callers follow scripted dialogues [13, 14]. The rest of the studies that used physical simulated patients trained their SPs accordingly. In total, the 19 included studies were made up of: 16 cross-sectional studies [13–28], one multi-centre cross sectional study [29], one dual-phased mixed method study [30], and one that did not mention its study design [31].
The studies were conducted in 13 countries, namely in Asia (n=7) [16, 18, 19, 26, 27, 29, 31], the Middle East (n=2)[20, 23], Africa (n=3)[13, 25, 30], Europe (n=3) [21, 24, 28], and North America (n=4) [14, 15, 17, 22].
The selected papers referred to SP differently. The terminologies used were: simulated patients (n=9)[15, 16, 18, 20–22, 26, 27, 31], simulated clients (n=6) [13, 19, 23, 25, 28, 29], standardised patients (n=1)[17], pseudo clients (n=1) [30] mystery shoppers (n=1), [24] and secret shoppers (n=1) [14].
Most of the papers performed SP studies in community pharmacies (n=12) [13, 16–21, 23, 28–31] Other medical facilities such as clinics (n=3)[14, 15, 26], and hospitals (n=1)[24] were also reported. One paper involved both clinic and hospital settings [27] and one paper conducted SP methods in all three of these settings [25]
Quality Assessment
Objective and execution
All 19 studies clearly stated the objective of research and their results and conclusions were aligned. Out of the 19 studies, six did not describe the SPs' backgrounds [14, 15, 25-28]. The findings are summarised in Table 2 and 3 for the price and non-price related characteristic, respectively.
Table 2. Comparison of study characteristics reported in the included studies (n=19)
No.
|
Country
|
Setting
|
Post Visit Acknowledgement
|
SP background
|
Terminology used
|
Discrepancies between information obtained from SP and questionnaire
|
|
1
|
Malaysia
|
Community pharmacy
|
Yes
|
Students
|
Simulated patient
|
Not specified
|
2
|
US
|
Community pharmacy
|
Yes
|
Nurses
|
Standardized patients
|
Not specified
|
3
|
Malaysia
|
Community pharmacy
|
No
|
Researchers
|
Simulated patient
|
Not specified
|
4
|
Indonesia
|
Community pharmacy
|
Yes
|
Volunteers
|
Simulated client
|
Not specified
|
5
|
Pakistan
|
Community pharmacy
|
No
|
Students
|
Simulated patient
|
Not specified
|
6
|
Germany
|
Community pharmacy
|
Yes
|
Students
|
Simulated patient
|
Not specified
|
7
|
The Gambia
|
Community pharmacy
|
Yes
|
Medical Research Council (MRC) Laboratories field worker
|
Simulated client
|
Not specified
|
8
|
US
|
Orthopedic practice
|
Yes
|
Research assistants
|
Simulated patient
|
Not specified
|
9
|
Qatar
|
Community pharmacy
|
Yes
|
Students
|
Simulated client
|
Not specified
|
10
|
Denmark
|
Hospital
|
Yes
|
Patients
|
Mystery shopper
|
Not specified
|
11
|
Kenya
|
Pharmacies, clinics, government health facilites
|
Yes
|
Not specified
|
Simulated client
|
Not specified
|
12
|
Ethiopia
|
Community pharmacy
|
Yes
|
Pharmacists
|
Pseudo client
|
Not specified
|
13
|
US
|
Clinics
|
No
|
Not specified
|
Secret shopper
|
Not specified
|
14
|
US
|
Clinics
|
No
|
Not specified
|
Simulated patient
|
Not specified
|
15
|
Thailand
|
Clinics
|
Yes
|
Not specified
|
Simulated patient
|
Not specified
|
16
|
Thailand
|
Private hospitals and clinics
|
No
|
Not specified
|
Simulated patient
|
Not specified
|
17
|
Turkey
|
Community pharmacy
|
Yes
|
Not specified
|
Simulated client
|
Not specified
|
18
|
Malaysia
|
Community pharmacy
|
Yes
|
Students
|
Simulated patient
|
Not specified
|
19
|
China
|
Community pharmacy
|
Yes
|
Research assistants
|
Simulated client
|
Not specified
|
|
|
|
|
|
|
|
|
|
|
|
|
Table 3. Comparison of price related parameters reported in the included studies (n=19)
No.
|
Drug type/ medical condition
|
Overview of the scenario
|
Dispensing fee (USD)
|
Price control policies
|
Selling price comparison with the recommended price
|
1
|
Common cold
|
Evaluate advice provision
|
None
|
ERP, VAT
|
Lower by 26%
|
2
|
Cancer
|
Evaluate advice provision
|
10
|
Fixed margin
|
Higher (no statistical data)
|
3
|
Back pain
|
Evaluate advice provision
|
None
|
ERP, VAT
|
Higher (no statistical data)
|
4
|
Antibiotics
|
Purchase medicine to determine quality
|
1 (prorated)
|
ERP, VAT
|
Lower by 34%
|
5
|
Insomnia
|
Evaluate advice provision
|
None
|
NA
|
No significant difference
|
6
|
Diarrhea (Loperamide)
|
Evaluating the quality of medicine dispensed
|
0.78
|
Price mark-up
|
Higher by 127%
|
7
|
STD
|
Evaluate advice provision
|
None
|
NA
|
Lower by 51%
|
8
|
Ankle fracture
|
Compare appointment price and availability of emergency department follow-up orthopedic care
|
10
|
Fixed margin
|
Higher by 30%
|
9
|
Acute respiratory condition
|
Evaluate advice provision
|
None
|
NA
|
No significant difference
|
10
|
Lower gastrointestinal diseases, acute orthopedic conditions
|
Evaluate advice provision
|
1.63
|
Price mark-up
|
No significant difference
|
11
|
Acute uncomplicated male urethritis
|
Assess STI treatment and HIV testing referral practices
|
None
|
NA
|
No significant difference
|
12
|
Headache
|
Evaluate advice provision
|
None
|
NA
|
Higher (no statistical data)
|
13
|
Buprenorphine and Methadone
|
Evaluate advice provision
|
10
|
Fixed margin
|
No significant difference
|
14
|
Knee osteoarthritis
|
Evaluate advice provision
|
10
|
Fixed margin
|
No significant difference
|
15
|
Stomach ache
|
Evaluate advice provision
|
None
|
ERP, VAT
|
Higher by 289%
|
16
|
Stomach ache
|
Evaluate advice provision
|
None
|
ERP, VAT
|
Higher by 777%
|
17
|
Diarrhea
|
Evaluate advice provision
|
None
|
Price mark-up
|
No significant difference
|
18
|
Malaysia Regulatory Classification Group B and C medicines
|
Access selling price of medicines
|
None
|
ERP, VAT
|
Lower by 35%
|
19
|
Antibiotics
|
Evaluate advice provision
|
None
|
ERP, VAT
|
No significant difference
|
*NA= Not applicable
Randomisation, blinding and follow-up
Of the 19 studies included in this review, none of them reported blinding of exposure or outcome. All of the SPs were revealed to the allocation status of the target medical facilities they were assigned to. No randomisation or follow-up studies were mentioned.
Validity
All of the studies (n=19) standardized their research by using formal scenarios. Written notes (n=12) were widely used to collect information [13, 16-21, 23-25, 28, 29]. Three studies used audiotape and written notes to record [26, 27, 30]. For the simulated phone call method (n=4), the SPs wrote down the responses while engaging in the conversation [14, 15, 22, 31]. To ensure validity, some studies (n=3) provided a questionnaire after the visits to obtain feedback from the medical officer or pharmacy staff [13, 24, 30].
Purpose of SP visits
The main purpose of SP visit is to obtain information on a drug/drugs actual selling price, by emulating a purchase based on medicine type or medical condition. 15 studies were designed based on medical conditions [13, 15-18, 20-28, 30]. Medical conditions included cancer, back pain, insomnia, diarrhoea, sexually transmitted diseases, ankle fractures, acute respiratory conditions, lower gastrointestinal diseases, acute orthopaedic conditions, acute uncomplicated male urethritis, headaches, knee osteoarthritis, and stomach aches. A total of four studies aimed to acquire information on certain prescription and non-prescription drugs such as buprenorphine, methadone, and antibiotics [14, 19, 29, 31].
Number of visits
The number of SP visits to medical facilities made in the included studies ranged from 24 to 371. The two studies that only used simulated phone calls involved 102 calls and 28651 calls, respectively. One study did not mention the number of visits made. The number of visits or sample size was determined by the purpose of visit. Studies that focused on evaluation or statistical analysis should have included a bigger number of observations. To test the quality of a service, for example, more visits would be required to ensure reliability [32].
Simulated patients and training
The number of SPs who participated in each study varied from 1 to 148. For the two simulated phone call-only studies, the number of simulated callers was nine and 102, respectively. Two studies did not state the number of SPs [20, 28]. Many used researchers, research assistants, nurses, pharmacists and fieldworkers who possessed pharmaceutical or medical backgrounds (n=6) [13, 17, 18, 22, 29, 30], and some obtained help from real patients or volunteers (n=2) [19, 24]. Some of the SPs were students in the medical field (n=5) [16, 20, 21, 23, 31] Most of the SPs were trained before actually visiting the medical facilities, except for the one study that used patients as SPs [24]. Scripts and scenarios were prepared before the real visits were carried out.
Ethics and consent
Among the 19 studies, only 14 stated that researchers obtained consent and ethical approval prior to the visits or calls [13, 16, 17, 19, 21-26, 28-31]. The remaining 5 studies did not provide information about ethical approval [14, 15, 18, 20, 27].
Selling price of drugs
All of the studies collected information on medicine prices. When compared with the recommended price, 37% (n=7) of the studies indicated that the prices of drugs recommended by the medical staff in some pharmacies or clinics were higher than the standard prices [17, 18, 21, 22, 26, 30]. Eight studies provided feedback that the costs of drugs across different pharmacies did not show significant differences [14, 15, 20, 23-25, 28, 29]. Four studies reported lower selling prices than the recommended prices from pharmaceutical authorities [13, 16, 19, 31].
Dispensing Fees
We also collected information on dispensing fees, which are professional fees charged by pharmacists whenever a prescription is filled [33]. The purpose of charging this fee is to compensate for the consultation given by the pharmacist. As it is difficult to quantify the extent of service, not every country applies a dispensing fee. In this review, only 4 countries, which appeared in 7 studies, have dispensing fees in their pharmaceutical system [14, 15, 17, 19, 21, 22, 24]: Denmark, Germany, Indonesia and the US. In 2021, this dispensing fee ranges from United States Dollar (USD) 0.78 to USD 10, with the lowest fee in Germany and the highest in the US.