Trust forms a cornerstone of the relationship between doctors and their patients. While widely recognized as essential and potentially fragile, the concept of patient trust hasn’t always been rigorously defined or measured. This article offers an overview of existing theories about patient trust and how it’s been measured over time. This information can be valuable for healthcare professionals, educators, and researchers in their practice and teaching. Identifying gaps in our current understanding of trust can guide future efforts to strengthen the methods used to study this critical aspect of medical relationships.
Trust is fundamental to any relationship between people, but it’s especially crucial in the doctor-patient relationship.1,2 Although most patients still believe doctors act in their best interests, there’s growing concern that rapid changes in healthcare are putting pressure on this trust and may be weakening it.1,3–5
These concerns highlight the urgent need to better understand the role of trust in healthcare. Where does patient trust remain strong? Where are the vulnerabilities that could negatively impact health outcomes? Despite numerous discussions and essays on trust, there hasn’t been extensive empirical research into patient trust. Furthermore, the methods for studying trust in the doctor-patient relationship are still in their early stages of development.
This paper aims to explore current theories about trust and synthesize the available research on doctor-patient trust, providing a practical, up-to-date look at current research methods and findings. We will briefly examine how research on patient trust has evolved, from early theoretical ideas to more recent empirical frameworks and measurable tools. Based on existing research, we will identify specific patient, doctor, and healthcare system factors known to influence trust. We will also discuss the impact of trust on healthcare delivery and patient health outcomes. Ultimately, our goal is to provide clinicians, educators, researchers, and policymakers with a concise summary of what we currently know about patient trust. This knowledge can then be used to improve the way we study trust and address the gaps in our understanding of this vital component of medical relationships and patient care.
DATA SOURCES
To gather information, we conducted an online search of the MEDLINE database (accessible at: www.nlm.nih.gov) using the keyword “patient-physician trust.” This initial search yielded 29 articles. Expanding on this, we used computer searches to find “similar” articles, which led to the identification of over 200 relevant articles. These were reviewed by the authors for this paper. Additionally, we engaged in informal discussions with leading experts in the field to pinpoint sources that have significantly influenced research, policy, and education in this area.
TRUST AS A CONCEPT: MANY THEORIES, LIMITED DATA
Patient trust is a complex and multifaceted idea that has been described in various ways. The different ways trust is understood and defined stem partly from the diverse theoretical backgrounds of academic fields like sociology and political science, which have studied trust in their own contexts.6–12 Even within specific fields, there’s considerable debate about how to define trust. Medical researchers are no different and have taken diverse approaches to defining trust in the doctor-patient relationship. Some theorists view patient trust as a set of beliefs or expectations about how a doctor will behave.13,14 Others emphasize the emotional side of trust, defining it as a patient’s reassuring sense of confidence or reliance in the doctor and their intentions.15 Commonly mentioned aspects of doctor behavior that influence patient trust include competence,1,3,5,13–15 compassion,1,3,14 privacy and confidentiality,1,13 reliability and dependability,13 and communication.16
A crucial distinction in understanding trust, particularly in doctor-patient relationships, is the difference between social trust and interpersonal trust.1,4 Interpersonal trust develops through repeated interactions, allowing expectations about a person’s trustworthiness to be tested over time.1 Social trust, on the other hand, is trust in broader institutions, shaped by media and general public confidence in these institutions. When considering a patient’s interpersonal trust in their doctor, it’s essential to consider the overall level of social trust in healthcare institutions like hospitals and HMOs. Theoretical work examining the connections between these types of trust emphasizes the critical role of social trust in shaping the traditional interpersonal trust between patients and doctors.17
While theoretical discussions about doctor-patient trust are abundant, there are limited research attempts to base the understanding of patient trust on actual patient experiences and viewpoints. A notable exception is the study by Thom and Campbell, who conducted focus groups with 29 patients from various practice settings.14 Participants were asked to share specific examples that either positively or negatively affected their trust in a doctor. The researchers identified nine dimensions of trust from patient accounts, ranging from technical skill and personal qualities to organizational factors. Most of these dimensions related to doctor behavior and demeanor. Patients indicated that trust was significantly influenced by their perceptions of doctor rapport, compassion, understanding, and honesty. Unsurprisingly, participants also confirmed the common idea that trust in doctors increases the likelihood of following treatment recommendations.
Image: A doctor and patient in a consultation, discussing medical information and treatment options, highlighting the importance of communication in building trust.
AVAILABLE MEASURES OF PATIENT TRUST
Currently, researchers have few rigorously developed and tested tools to measure patient trust. The first instrument specifically designed to measure trust in the doctor-patient relationship appeared in 1990.13 These researchers developed and validated an interview tool to measure an individual’s trust in their primary care physician. Following thorough instrument review and patient interviews, they created 25 initial statements intended to assess trust based on real-life experiences. The final instrument, called the Trust in Physician Scale, is an 11-item, interviewer-administered questionnaire. It evaluates patient trust in terms of dependability, confidence, and information confidentiality. All items use a 5-point Likert scale and include a mix of positively and negatively worded questions (see Table 1). Items were included in the final instrument only if they showed high response variation and a correlation of .40 or greater with the total score. The 11-item scale demonstrated high internal consistency, with Cronbach’s alpha coefficients of 0.85 or higher in two separate item analyses. Construct validity was also assessed twice by comparing scores on the Trust in Physician Scale with scores on similar concepts related to doctor-patient relationships. The strong psychometric properties of the Trust in Physician Scale have made it a benchmark for developing future measures.
Table 1.
Instruments for Assessing Patient Primary Care Assessment Survey
| Trust in Physician Scale(Anderson and Dedrick)13 | Primary Care Assessment Survey(Safran)18 | Patient Trust Scale (Kao)2 |
|---|---|---|
| How much do you trust your physician(s)… | ||
| 1. I doubt that my doctor really caresabout me as a person. | 1. I can tell my doctor anything. | 1. To put your health and well-beingabove keeping down the healthplan’s costs? |
| 2. My doctor is usually considerate ofmy needs and puts them first. | 2. My doctor sometimes pretends toknow things when he/she is reallynot sure. | 2. To keep personally sensitivemedical information private? |
| 3. I trust my doctor so much that Ialways try to follow his/her advice. | 3. I completely trust my doctor’sjudgment about my medical care. | 3. To provide you with informationon all potential medical options andnot just options covered by thehealth plan? |
| 4. If my doctor tells me something isso, then it must be true. | 4. My doctor cares more about holdingcosts down than about doing what is needed for my health. | 4. To refer you to a specialist whenneeded? |
| 5. I sometimes distrust my doctor’sopinion and would like a second one. | 5. My doctor would always tell me thetruth about my health, even if therewas bad news. | 5. To admit you to the hospital whenneeded? |
| 6. I trust my doctor’s judgment aboutmy medical care. | 6. My doctor cares as much as I doabout my health. | 6. To make appropriate medicaldecisions regardless of health planrules and guidelines? |
| 7. I feel my doctor does not doeverything he/she should for mymedical care. | 7. If a mistake was made in mytreatment, my doctor would try tohide it from me. | 7. Judgment about your medical care? |
| 8. I trust my doctor to put mymedical needs above all otherconsiderations when treating mymedical problems. | 8. All things considered, how much doyou trust your doctor? | 8. To perform necessary medical testsand procedures regardless of cost? |
| 9. My doctor is a real expert in takingcare of medical problems like mine. | 9. To offer you high-quality medicalcare? | |
| 10. I trust my doctor to tell me if amistake was made about mytreatment. | 10. To perform only medicallynecessary test and procedures. | |
| 11. I sometimes worry that my doctormay not keep the information wediscuss totally private. |
Doctor-patient trust has also been assessed in studies examining various aspects of the doctor-patient relationship simultaneously. The Primary Care Assessment Survey (PCAS) is a prominent example. Developed by Safran and colleagues, this self-administered questionnaire was used to study primary care quality across different healthcare systems, including indemnity and managed care.18 Similar to the Trust in Physician Scale, the PCAS focuses on trust within a specific doctor-patient relationship over time, rather than during a single visit or episode of care. The PCAS includes 11 summary scales, with 51 questions in total, measuring seven key aspects of primary care quality, including trust. The trust subscale consists of eight Likert-scale questions designed to assess integrity, agency, and competence (see Table 1).
Pilot studies evaluated all 11 PCAS summary scales for data completeness, score distribution, and interscale correlations. Detailed psychometric analyses demonstrated excellent performance for all subscales, including trust. Cronbach’s alpha coefficients for each subscale exceeded the statistical criteria for internal consistency, ranging from 0.81 to 0.95.
The Patient Trust Scale, developed by Kao and colleagues, is the most recent addition to validated measures of doctor-patient trust.2,19 This scale is gaining attention due to its use in recent reports evaluating how payment methods and managed care impact patient trust. For these studies, Kao and colleagues initially created a 16-item scale (unpublished data), modifying items from Anderson and Dedrick’s Trust in Physician Scale and adding new items related to confidentiality, reliability, and patients’ trust in their doctors to provide necessary care despite cost concerns and administrative limitations. This 16-item scale was tested in a pilot study of 292 patients. Psychometric analysis led to a refined 10-item scale with a Cronbach’s alpha of 0.94.
Kao’s 10-item Patient Trust Scale reflects current concerns about managed care. Developed for a study on the impact of payment systems on trust, it heavily emphasizes questions about how cost-consciousness affects doctors’ ability to act in their patients’ best interests (see Table 1). Some aspects of trust identified by previous researchers are less emphasized or absent in this scale. For instance, many dimensions identified by Thom from patient focus groups, such as trust in technical competence, understanding patient experiences, expressing care, clear communication, shared decision-making, and honesty/respect, are not included. Anderson and Dedrick’s Trust in Physician Scale includes a question about willingness to follow doctor’s advice, which is absent in Kao’s scale. Similarly, Safran’s PCAS trust subscale includes truth-telling and willingness to disclose information, which are also not covered in Kao’s instrument. Researchers considering using these validated measures should be aware of these important distinctions, primarily arising from their differing emphasis on the various dimensions of trust.
CORRELATES OF TRUST
Despite extensive research on patient satisfaction, the limited empirical research on trust provides little data on clear factors associated with doctor-patient trust. Furthermore, there are no published studies to date on successful interventions that have demonstrably improved patient trust in their doctors.
Some of the most informative data on factors related to doctor behavior and patient trust come from evaluations of the PCAS instrument.18 The patient trust subscale showed the strongest correlations with patient ratings of doctor communication (0.75), interpersonal treatment (0.73), and knowledge of the patient (0.68). Correlations between trust and continuity of the doctor-patient relationship (0.22), preventive counseling (0.25), and patient financial access to care (0.29) were notably lower.
Recently, there’s growing interest in how healthcare systems impact patient trust, especially concerning changes from managed care. Grumbach and colleagues, using a single 5-point Likert scale to measure trust in a California survey, found that patients reporting difficulty getting referrals were more likely to report low trust in their primary care doctors (adjusted odds ratio, 2.7; 95% confidence interval, 2.1 to 3.5).20 Kao and colleagues, using both versions of their newly developed trust measure, have published two studies on patient trust. Multivariate analyses revealed several independent factors associated with trust, although findings were not always consistent. In their first study of 292 participants, patients reporting sufficient choice of doctor (P<0.01), satisfaction with information received (P<0.05), and trust in their health plan (P<0.001) had significantly higher trust in their doctors. Interestingly, payment method (fee-for-service vs. managed care) was not significantly associated with trust in this study.
Kao’s second study, involving 2,086 patients, used the shorter 10-item scale. The main finding was that more fee-for-service indemnity patients (94%) completely or mostly trusted their doctors to “put their health and well-being above keeping down the health plan’s costs” compared to salary (77%), capitated (83%), or fee-for-service managed care patients (85%). These differences remained significant in multivariate analyses but were considerably reduced when the model included a measure of doctor behavior from the Picker survey on patient-centered care.21 In other words, while payment structure was linked to patient trust, this link lessened significantly when considering the doctor’s interpersonal style. Similar to their first study, Kao and colleagues found that patient trust also correlated with trust in the health plan, length of the doctor-patient relationship, and patient choice of doctor. In contrast to the first study, trust was also significantly associated with being white (higher trust) and self-reported health status (better health linked to higher trust).
Although doctor behavior and interpersonal skills are widely believed to be crucial for patient trust, only one published article examines a trial aimed at improving doctor trust-building skills, and the results were not encouraging.22 Thom and colleagues enrolled over 400 adult patients from 20 community-based family physician practices. Half of the doctors were randomly chosen to attend a one-day continuing medical education workshop focused on improving skills for building and maintaining patient trust. Primary outcomes included doctor behavior, patient satisfaction, and trust, measured using the Trust in Physician Scale. None of the primary outcomes, including trust, showed significant changes from before to after the intervention, nor were there significant differences between the intervention and control groups.
Image: A doctor reassuring a patient, demonstrating empathy and building a trusting relationship, emphasizing the role of interpersonal skills in fostering trust.
HEALTH OUTCOMES ASSOCIATED WITH TRUST
Trust is considered a valuable outcome in itself, and some researchers have investigated its positive effects on health behaviors and outcomes. Theoretically, patient trust should strengthen the doctor-patient relationship as a health partnership, increasing patient satisfaction, treatment adherence, and improved health, while reducing the likelihood of patients leaving the practice or health plan.
However, only one published report has assessed doctor-patient trust as a predictor of other health outcomes. Safran and colleagues used the PCAS to examine the relationship between seven key elements of primary care, including trust, and three outcomes: self-reported adherence to doctor’s advice, patient satisfaction with doctor, and improved health status.23 While they couldn’t demonstrate a direct link between patient trust and improved health status, trust was one of the strongest predictors of satisfaction with the doctor and adherence to treatment. Adherence rates were 43.1% among patients with trust scores in the 95th percentile, compared to only 17.5% in patients with trust scores in the 5th percentile. For satisfaction, patient trust was the most strongly associated factor. Patients with 95th percentile trust scores were about five times more likely to express complete satisfaction with their doctors compared to those with median trust levels (87.5% vs. 18.4%, P<0.001).
As Safran and colleagues note, their findings don’t prove a causal relationship between trust and the outcomes studied. Nevertheless, their results suggest that trust is a vital component of doctor-patient relationships that enable excellent healthcare delivery.
CONCLUSION
The importance of trust in doctor-patient relationships is undeniable. However, our understanding has largely relied on the insights and personal experiences of doctors who value the special connection with their patients. For practicing clinicians and educators in medical schools and residency programs, the elements of doctor behavior that build trust continue to reflect the intuitive wisdom of physician-theorists: competence, compassion, reliability, integrity, and open communication.
A universally accepted empirical understanding and definition of trust is still evolving. In recent years, other complex and once considered intangible concepts like “satisfaction”24,25 and “health status”26,27 have been successfully studied using rigorous qualitative and quantitative methods. Researchers and policymakers now have standardized tools to measure these concepts across various healthcare settings. While efforts to operationalize doctor-patient trust are still in their early stages, with models emerging from researchers like Kao and Safran, the refinement and convergence of these methods may soon allow trust to be measured and discussed as routinely and rigorously as other aspects of healthcare. Strengthening doctor-patient trust requires further development in our ability to measure both the factors that influence trust and its outcomes.
However, a single measure of patient trust is unlikely to become dominant, nor should it. The ever-changing healthcare landscape will continue to shed new light on doctor-patient relationships. New challenges to trust will emerge, while others may become less significant. Just as overly paternalistic doctors were a primary concern in the 1970s, researchers are now more focused on measuring patient concerns about doctors’ potential conflicts of interest due to financial incentives. As the focus of trust measures has evolved, from the earliest measure by Dedrick and Anderson to the latest by Kao et al., measures of doctor-patient trust must continue to adapt to changes in healthcare and societal views on the key components of trust.
