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It is now common practice for doctors to consult patients by means other than face-to-face, often appearing before the patient on a computer screen. Also, many websites are using depictions of health professionals to increase the credibility of their services. Being trustworthy is an essential attribute for successful ehealth services. Little is known about which depicted accessories make a health professional appear more trustworthy.
To estimate the odds of an individual on-screen being rated trustworthy when viewed in a static image holding or wearing specific items of medical equipment.
We surveyed consecutive people attending community pharmacies to collect prescriptions in Western Australia. Respondents were presented with a series of 10 photographs, generated at random, of a man with varying numbers and combinations of medical equipment: stethoscope, reflex hammer, surgical scrubs, otoscope, and pen. They were then invited to rate the man as honest, trustworthy, honorable, moral, ethical, or genuine, or a combination of these, on the Source Credibility Scale.
A total of 168 of 250 people gave informed consent, for a participation rate of 67.2%. There were 102 female and 66 male respondents. Of the 168 respondents, 96 (57%) were born in Australia and 102 (60.7%) were attending medical practices with more than one general practitioner. The mean age of respondents was 47 (SD 16) years (range 26–92 years). When only 1 item was present in an image, the stethoscope was associated with the highest odds for the person being considered honest (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.6–4.3), trustworthy (OR 2.3, 95% CI 1.4–3.8), honorable (OR 2.7, 95% CI 1.6–4.5), moral (OR 2.4 95% CI 1.4–4.1), ethical (OR 2.6, 95% CI 1.5–4.6), and genuine (OR 1.8, 95% CI 1.0–3.1). The presence of a stethoscope increased the odds of the person being rated in a positive light in all photographs in which it was included.
When an individual is portrayed in a static image, concurrent presentation of 3 or more items of medical equipment, and especially a stethoscope, is likely to exert a positive influence on the viewers’ perceptions of the qualities of the person depicted.
When people are concerned about their physical or psychological well-being, they may consult a doctor. When a patient consults a doctor face-to-face, all five senses affect the experience: sight, hearing, touch, smell (eg, medications, disinfectants, and tissues), and sometimes taste (eg, medications, and equipment used to examine the mouth or throat) [
When someone is experiencing symptoms, the condition does not require the presence of objective organic pathological analysis. Indeed, some people experience relief from symptoms despite being treated with a placebo or inactive drug [
The literature records many studies in which credibility and persuasive communication have been tested with specific reference to the physical appearance of doctors. In an experiment conducted by computer scientists, advice was shown to be much more persuasive when presented as coming from doctors as depicted in static pictures [
In addition to what the doctor is wearing, we must also consider what he or she is seen to be holding, or using. For example, the stethoscope has been the cornerstone of medical diagnostics for nearly 200 years. This monaural device improved physicians’ ability to hear clues to their patients’ underlying pathology and thus apply the appropriate treatment in many cases. It has been eulogized by many commentators, such as the following:
The stethoscope is one of several medical instruments that are recognized by laypeople as belonging in a doctor’s office and that have significance in the consultation that extends beyond the instrument’s physical functionality. Similarly, reflex hammers and other items used in clinical examination have developed an iconic status for doctors [
We obtained human research ethics approval from Curtin University (approval number RD-23-10) before commencing the study. All respondents provided consent before data collection. Consecutive people waiting in six community pharmacies to collect prescriptions for drugs prescribed by a doctor were presented with a series of photographs on an iPad. Each photograph presented an image of a man with a neutral facial expression who was wearing a casual shirt. Some of the images contained medical equipment. The respondents were not told anything about the person in the photograph. The photographs were presented as a series of 10 consecutive images containing an increasing number of items of medical equipment ranging from 0 to 5. Each series of 10 was unique to each participant and drawn at random from a pool of images. The equipment (collectively called icons here) consisted of a stethoscope, otoscope, reflex hammer, surgical scrubs, and pen. We chose these icons from the list of items that have been recommended as necessary in a general practitioner’s bag [
The participants were invited to rate the individual using the trustworthiness measure of the Source Credibility Scale (SCS) [
Example of an image shown to the respondents.
Elements of the Source Credibility Scale.
For logistic regression, to estimate the odds of a specific outcome within 80% confidence intervals at 5% significance, in this case scoring an image as trustworthy and modeling 11 explanatory variables, we required 138 respondents based on a moderate effect size [
We used ordinal logistic regression to examine the influence on primary outcomes of icons presented in the photos. The influence was calculated as the odds of a person being rated honest, trustworthy, honorable, moral, ethical, or genuine, or a combination of these, after adjusting the respondents’ characteristics (eg, sex, age group, and country of birth). Five predictor variables (the icons, ie, the stethoscope, otoscope, reflex hammer, surgical scrubs, and pen) were assessed after controlling for respondents’ demographics and experience of consulting doctors. This consulting experience included the type of medical practice frequented (solo practitioner or group practice), number of general practitioner visits, and number of hospital visits.
Regression analysis was performed to assess the effect of the 5 icons and the different combinations of icons on rating for honest, trustworthy, etc. A variable that defined the 5 icons (model 1), the different combination of icons (2 icons, 3 icons, 4 icons: models 2–4), and all 5 icons (model 5) were used in the corresponding models. In each model, the group of vignettes (photographs) with no icon was treated as the reference group, and the groups of vignettes with 1, 2, 3, 4, or 5 icons were compared with the reference group respectively in the regression model. The lack of independence between individual participants, which causes intragroup correlation, was adjusted in the models through estimating the clustered robust standard errors. Statistical analysis was performed using Stata Statistical Software (IC 11.1; State Corp LP, College Station, TX, USA).
We invited 250 people to participate, and 168 completed the survey, giving a participation rate of 67.2%. Demographic details are presented in
Demographic characteristics of respondents (n = 168).
Characteristic | n | % |
|
|
|
.64 | |||
≤45 | 81 | 48% | ||
>45 | 87 | 52% | ||
|
.006 | |||
Male | 66 | 39% | ||
Female | 102 | 60.7% | ||
|
.06 | |||
Australia | 96 | 57% | ||
Other | 72 | 43% | ||
|
.006 | |||
Clinic with more than one general practitioner | 102 | 60.7% | ||
Solo practitioner | 66 | 39% |
a
Data for person in photograph being perceived as honest and trustworthy when 1 or more iconsa are present versus no icons.
Model | Honest | Trustworthy | |||
ORb | 95% CIc | OR | 95% CI | ||
|
|||||
S | 2.6 | 1.6–4.3*** | 2.3 | 1.4–3.8*** | |
O | 1.6 | 1.1–2.4* | 1.4 | 0.9–2.3 | |
RH | 1.5 | 0.9–2.5 | 1.6 | 1.0–2.5* | |
SS | 1.3 | 0.8–2.1 | 1.2 | 0.8–1.9 | |
|
1.3 | 0.8–2.1 | 1.2 | 0.8–2.0 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+RH | 3.9 | 2.1–7.4*** | 2.3 | 1.1–4.6* | |
S+SS | 2.5 | 1.5–4.3*** | 1.3 | 0.7–2.5 | |
S+P | 2.5 | 1.3–4.8** | 2.7 | 1.5–4.8*** | |
O+RH | 2.9 | 1.7–4.9*** | 1.8 | 0.9–3.4 | |
O+P | 1.8 | 0.8–3.7 | 2.3 | 1.2–4.3* | |
RH+SS | 2.5 | 1.3–4.8** | 1.4 | 0.6–3.1 | |
RH+P | 1.8 | 0.9–3.4 | 1.8 | 1.0–3.2e | |
SS+P | 1.7 | 0.9–3.4 | 1.9 | 1.0–3.5e | |
O+P | 2.4 | 1.0–5.5* | 4.0 | 2.3–7.0*** | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH | 3.0 | 1.6–5.7*** | 3.1 | 1.6–5.8*** | |
S+O+RH | 4.0 | 2.3–6.8*** | 2.3 | 1.3–4.2** | |
S+O+P | 4.0 | 2.1–7.6*** | 3.9 | 2.0–7.5*** | |
S+RH+SS | 2.6 | 1.3–5.1** | 2.8 | 1.5–5.2*** | |
S+RH+P | 2.3 | 1.0–5.1* | 2.2 | 1.1–4.5* | |
S+SS+P | 3.4 | 1.8–6.4*** | 2.7 | 1.4–5.4** | |
O+SS+P | 1.8 | 0.7–4.5 | 1.7 | 0.5–5.3 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH+SS | 4.4 | 2.5–7.7*** | 2.6 | 1.4–4.9** | |
S+O+RH +P | 4.0 | 2.5–6.4*** | 3.0 | 1.9–4.8*** | |
S+O+SS+P | 3.7 | 2.2–6.1*** | 3.6 | 2.3–5.7*** | |
S+RH+SS+P | 2.1 | 1.3–3.4** | 2.8 | 1.8–4.6*** | |
O+RH+SS+P | 3.4 | 1.9–6.2*** | 1.6 | 0.8–3.2 | |
No icond | 1.0 | 1.0 | |||
|
3.7 | 2.4–5.5*** | 3.7 | 2.5–5.5*** | |
No icond | 1.0 | 1.0 |
a Icons are as follows: S = stethoscope, O = otoscope, RH = reflex hammer, SS = surgical scrubs,
b Odds ratio.
c Confidence interval.
d Photo with no icon group was the reference group for each of the models.
e 95% CI was rounded to 1.00 but the
*
Data for person in photograph being perceived as honorable and moral when 1 or more iconsa are present versus no icons.
Model | Honorable | Moral | |||
ORb | 95% CIc | OR | 95% CI | ||
|
|||||
S | 2.7 | 1.6–4.5 | 2.4 | 1.4–4.1** | |
O | 1.3 | 0.8–2.1 | 1.3 | 0.8–2.2 | |
RH | 1.6 | 1.0–2.6e | 1.7 | 1.1–2.6* | |
SS | 1.3 | 0.8–2.2 | 1.4 | 0.9–2.3 | |
|
1.7 | 1.0–2.6* | 1.1 | 0.7–1.8 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+RH | 2.2 | 1.1–4.5* | 2.1 | 1.1–4.1* | |
S+SS | 2.5 | 1.5–4.2*** | 2.0 | 1.2–3.4** | |
S+P | 1.7 | 0.9–3.3 | 2.2 | 1.3–4.0** | |
O+RH | 2.4 | 1.3–4.5** | 2.4 | 1.4–4.3** | |
O+P | 1.9 | 0.9–3.7 | 1.5 | 0.7–3.5 | |
RH+SS | 2.3 | 1.1–4.7* | 2.0 | 1.0–4.0e | |
RH+P | 2.7 | 1.3–5.6** | 2.7 | 1.4–5.0** | |
SS+P | 2.7 | 1.4–5.1** | 2.5 | 1.4–4.5** | |
O+P | 1.7 | 0.7–4.0 | 1.9 | 0.8–4.3 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH | 3.5 | 1.9–6.6*** | 3.3 | 1.8–6.1*** | |
S+O+SS | 3.0 | 1.7–5.5*** | 2.9 | 1.6–5.1*** | |
S+O+P | 2.4 | 1.2–5.1* | 2.3 | 1.1–5.1* | |
S+RH+SS | 3.0 | 1.5–6.0** | 2.5 | 1.3–5.0** | |
S+RH+P | 2.4 | 1.1–5.1* | 2.1 | 1.0–4.3* | |
S+SS+P | 4.2 | 2.3–7.6*** | 3.9 | 2.2–7.1*** | |
O+SS+P | 2.3 | 1.1–5.1* | 2.0 | 1.0–4.0e | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH+SS | 3.7 | 2.0–6.9*** | 3.6 | 2.0–6.5*** | |
S+O+RH+P | 3.3 | 2.0–5.5*** | 3.0 | 1.9–4.8*** | |
S+O+SS+P | 2.6 | 1.6–4.3*** | 2.5 | 1.5–4.2*** | |
S+RH+SS+P | 2.4 | 1.4–3.9*** | 1.8 | 1.1–3.1* | |
O+RH+SS+P | 3.6 | 2.0–6.4*** | 3.4 | 2.1–5.7*** | |
No icond | 1.0 | 1.0 | |||
|
3.1 | 2.1–4.6*** | 3.1 | 2.2–4.4*** | |
No icond | 1.0 | 1.0 |
a Icons are as follows: S = stethoscope, O = otoscope, RH = reflex hammer, SS = surgical scrubs,
b Odds ratio.
c Confidence interval.
d Photo with no icon group was the reference group for each of the models.
e 95% CI was rounded to 1.00 but the
*
Data for person in photograph being perceived as ethical and genuine when 1 or more iconsa are present versus no icons.
Model | Ethical | Genuine | |||
ORb | 95% CIc | OR | 95% CI | ||
|
|||||
S | 2.6 | 1.5–4.6*** | 1.8 | 1.0–3.1* | |
O | 1.7 | 1.0–2.8e | 1.4 | 0.9–2.3 | |
RH | 1.5 | 0.9–2.6 | 1.7 | 1.1–2.6* | |
SS | 1.2 | 0.7–2.1 | 1.3 | 0.8–2.0 | |
|
1.3 | 0.8–2.1 | 0.9 | 0.5–1.5 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+RH | 2.8 | 1.4–5.7** | 2.1 | 1.1–4.0* | |
S+SS | 1.6 | 0.9–3.1 | 1.3 | 0.7–2.4 | |
S+P | 2.8 | 1.5–5.1*** | 2.5 | 1.4–4.1*** | |
O+RH | 2.1 | 1.1–4.3* | 1.5 | 0.7–3.2 | |
O+P | 2.8 | 1.4–5.5** | 2.3 | 1.2–4.3* | |
RH+SS | 2.9 | 1.4–5.7** | 2.7 | 1.4–5.2** | |
RH+P | 2.6 | 1.4–4.5*** | 1.8 | 1.0–3.2* | |
SS+P | 2.8 | 1.4–5.5** | 2.0 | 1.0–3.9e | |
O+P | 3.7 | 2.1–6.7*** | 3.5 | 1.6–7.6*** | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH | 3.3 | 1.8–5.9*** | 2.4 | 1.3–4.1** | |
S+O+SS | 2.6 | 1.4–5.0** | 2.1 | 1.1–3.8* | |
S+O+P | 3.4 | 1.8–6.4*** | 3.1 | 1.6–5.7*** | |
S+RH+SS | 3.2 | 1.6–6.3*** | 2.9 | 1.6–5.3*** | |
S+RH+P | 2.1 | 0.9–4.6 | 1.7 | 0.7–4.1 | |
S+SS+P | 3.4 | 1.8–6.7*** | 2.5 | 1.2–5.4* | |
O+SS+P | 2.3 | 1.0–5.4e | 1.5 | 0.7–3.3 | |
No icond | 1.0 | 1.0 | |||
|
|||||
S+O+RH+SS | 3.5 | 2.0–6.2*** | 2.9 | 1.6–5.1*** | |
S+O+RH+P | 2.9 | 1.7–5.0*** | 2.6 | 1.6–4.3*** | |
S+O+SS+P | 3.1 | 1.9–5.0*** | 2.6 | 1.6–4.3*** | |
S+RH+SS+P | 2.9 | 1.8–4.8*** | 2.5 | 1.6–3.9*** | |
O+RH+SS+P | 2.4 | 1.3–4.5** | 1.8 | 1.0–3.5e | |
No icond | 1.0 | 1.0 | |||
|
4.1 | 2.8–5.9*** | 3.1 | 2.2–4.5*** | |
No icond | 1.0 | 1.0 |
a Icons are as follows: S = stethoscope, O = otoscope, RH = reflex hammer, SS = surgical scrubs,
b Odds ratio.
c Confidence interval.
d Photo with no icon group was the reference group for each of the models.
e 95% CI was rounded to 1.00 but the
*
When only 1 icon was presented in the photograph, the stethoscope was associated with the highest odds for the person being considered honest, trustworthy, moral, honorable, ethical, or genuine, or a combination of these. The stethoscope evoked strong positive perceptions. There were no differences in scores on any characteristics for any combination of 2 icons. However, photographs with 3 or more icons had significantly higher scores for all characteristics than photographs with 0 or 1 icon. Literature on the impact of prominently displaying icons in medical consulting rooms concluded that they may determine the extent to which a doctor is perceived to be open to the ideas, concerns, and expectations of the patient in the consultation [
The same images, albeit a limited random selection, were shown to all respondents. This is a possible limitation because the demand characteristics placed on the participants may have been enough to explain the increasing trustworthiness ratings with increasing number of medical devices in the photographs. The participants may have worked out that their ratings were supposed to be based on the changing elements of the pictures and that more devices should indicate greater trustworthiness. However, the relative trustworthiness ratings of types of devices might be free from demand characteristics, and we were able to estimate this from the data. The demographic characteristics of the respondents were similar to those of patients who generally visit general practitioners in Australia, and most were women over 45 years of age [
In this study we introduced participants to a series of photographs of a person along with a variety of items associated with doctors. These items were used because they are commonly recognized symbols or icons of medical practice that patients use to make meaning of a medical consultation. In Peircean semiotics, each of the items we employed is more properly an index because the item is connected directly in some way to the functions we ascribe to doctors, and hence the signifier is not entirely arbitrary [
When doctors appear in static images, 3 or more icons of medical equipment may be helpfully included in the images, one of which should be a stethoscope. These icons are likely to have a positive influence on patients’ perceptions of the trustworthiness of the practitioner.
No icon.
Otoscope.
Reflex hammer.
Pen.
Stethoscope.
Surgical scrubs.
confidence interval
odds ratio
Source Credibility Scale
We acknowledge the support of Zaminah Khadaroo, Dr Wendy Chan She-Ping Delfos, and Christopher Kueh in developing the materials for this study and in data collection. We thank Dr David Lim, Ms Lucy Wilkie, and Ms Deepa Sriram for support in preparing the manuscript.
Funding: Curtin University.
None declared.