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Internet sources are becoming increasingly important in seeking health information, such that they may have a significant effect on health care decisions and outcomes. Hence, given the wide range of different sources of Web-based health information (WHI) from different organizations and individuals, it is important to understand how information seekers evaluate and select the sources that they use, and more specifically, how they assess their credibility and trustworthiness.
The aim of this study was to review empirical studies on trust and credibility in the use of WHI. The article seeks to present a profile of the research conducted on trust and credibility in WHI seeking, to identify the factors that impact judgments of trustworthiness and credibility, and to explore the role of demographic factors affecting trust formation. On this basis, it aimed to identify the gaps in current knowledge and to propose an agenda for future research.
A systematic literature review was conducted. Searches were conducted using a variety of combinations of the terms WHI, trust, credibility, and their variants in four multi-disciplinary and four health-oriented databases. Articles selected were published in English from 2000 onwards; this process generated 3827 unique records. After the application of the exclusion criteria, 73 were analyzed fully.
Interest in this topic has persisted over the last 15 years, with articles being published in medicine, social science, and computer science and originating mostly from the United States and the United Kingdom. Documents in the final dataset fell into 3 categories: (1) those using trust or credibility as a dependent variable, (2) those using trust or credibility as an independent variable, and (3) studies of the demographic factors that influence the role of trust or credibility in WHI seeking. There is a consensus that website design, clear layout, interactive features, and the authority of the owner have a positive effect on trust or credibility, whereas advertising has a negative effect. With regard to content features, authority of the author, ease of use, and content have a positive effect on trust or credibility formation. Demographic factors influencing trust formation are age, gender, and perceived health status.
There is considerable scope for further research. This includes increased clarity of the interaction between the variables associated with health information seeking, increased consistency on the measurement of trust and credibility, a greater focus on specific WHI sources, and enhanced understanding of the impact of demographic variables on trust and credibility judgments.
People are increasingly seeking health information and advice online. Statistics from the Pew Research Center show that one in three adults in the United States go online to try to identify a diagnosis or to know more about a health complaint [
Given the importance of the evaluation of WHI, and more specifically the role of trust and credibility judgments, there is a growing body of research in this area, and therefore, a continuing need to develop coherent reviews of the field as a basis for further research and to inform practice. Hence, this article undertakes a systematic literature review of the research that features the concepts of trust and credibility in WHI seeking. More specifically, it seeks to answer the following research questions:
RQ1: What is the profile of the research conducted on trust and credibility in WHI seeking?
RQ2: Which factors have been identified as impacting on judgments of trustworthiness and credibility in WHI seeking?
RQ3: Which factors, alongside trust and credibility, have been identified as influencing WHI seeking?
RQ4: What demographic factors affect trust formation in WHI seeking?
Given the importance of the trustworthiness of the health information gathered from digital sources, other authors have conducted literature reviews on this and related topics. Most of these were conducted a few years ago and, while retaining significant reference value, require updating [
Another unique and important aspect of this review is its scope, in that it embraces both trust and credibility. Most prior reviews, and indeed much of the research, distinguishes between trust and credibility. Furthermore, for some authors, trust is defined as an antecedent to credibility (eg, [
As suggested above, there are many definitions of trust and credibility in literature. This section provides some examples to orientate the reader and give context to this research. Tseng and Fogg [
A systematic literature review was carried out to highlight and explore the various aspects and applications of the concept of “trust” in digital health information. The review protocol selected was that proposed by Tranfield et al [
Review protocol: databases.
Type of database | Database name | Search fields | Number of final records | |
Multidisciplinary | Scopus | Title and abstract and keywords | 932 | |
ScienceDirect | Title and abstract and keywords | 117 | ||
Web of Science | Title and topic | 787 | ||
ProQuest | All-except full text | 1208 | ||
Health-focus | Medline | Title and keywords | 313 | |
PubMed | Title and abstract | 254 | ||
PsycINFO | Title and abstract | 211 | ||
Cochrane Library | Title and abstract and keywords | 5 | ||
Total number of records | 3827 |
An exhaustive series of search strings was employed in each database, accounting for synonyms, plurals, hyphenations, and multiple word combinations (eg, “information quality” or “quality of information,” and “ehealth” and its variants “e-Health” or “e-health”). Numerous combinations of words and strings were applied with Boolean operators “AND” and “OR” to broaden the search. Over 20 searches were conducted. Examples include:
[online health information] AND [trust]
[digital health information] AND [credibility]
[web health information] AND [information quality]
[health information] AND [trust] AND [online] OR [electronic]
The search exercise, conducted in July 2016 on academic, peer-reviewed literature written in English from the year 2000 onward, identified a total of 3827 records (
Next, an iterative process of refinement and exclusion was carried out on the records to optimize the emphasis on the proposed research topic. Each record (ie, titles, keywords, and abstracts) was scanned for relevance and source, and all articles off-topic, without a full citation, and written in languages other than English were discarded. All conference proceedings papers, books, and book chapters were also discarded, except for 2 conference papers that were retained because of their high citation rate ([
Search procedure for articles on trust and credibility in Web-based health information.
This section summarizes key aspects of the bibliographic profile of the literature (RQ1) before further elaboration on the topics covered by this research in response to the remaining research questions (RQ2, RQ3, and RQ4), which are discussed further below.
This section profiles the dataset in terms of the research methodologies used, and the distribution of articles over time, by discipline and by country.
The majority of the titles (71 articles) in the final dataset were empirical studies largely conducted by means of quantitative research instruments (55 articles); nine studies were qualitative, seven used mixed-method approaches, and two were conceptual articles. The participants for the empirical studies were, in almost half of the cases (37/71 articles), adults between 18 and 65 years of age. Undergraduate students were the subject of the research in 20 articles and older people (usually 50-55 years and over) were studied in eight articles. Two studies [
In addition, there is no agreement on how trust and credibility are measured among different authors. For example, in 2007, Flanagin and Metzgen [
The final dataset was then categorized in terms of journal subject area, defined according to Scopus’ Scimago Journal and Country Rank (SJR) website (
Article distribution by journal area of research. This chart has been informed by the Scopus-defined journal subject areas. The overall number of titles exceeds 73 because many journals have more than one subject area.
All articles were also categorized on the basis of the country where the bulk of the research was carried out (
There is an established acknowledgment of the importance of research into trust and credibility in WHI seeking, and the number of publications has increased over the last 15 years, although slowly and with setbacks. The number of publications in the dataset never exceeded nine articles in any given year (
Article distribution by journal area of country.
Publication of articles over time.
The 34 articles in this category argue that trust (or credibility) can be defined as the end result of a series of judgments people apply during their online search processes. Such judgments are usually exercised on both the design features of websites and the content features of the information found.
There might be some overlap between the features identified as design and those as content, due to the personal interpretation that some authors provide of certain aspects. For example, discussion groups could be classed as a content feature, implying access to information created by other peers rather than professionals, and indeed, Sillence et al’s [
When discussing design features, many authors agree that a clear layout of the website is a strong positive factor influencing trust formation; the presence of contact details and the authority of the owner of the website follow as the second and third most cited factors to consider when addressing trust or credibility issues. The availability of interactive features is another desirable trait of Web design, but it should be noted that the concept of “interactive” has been evolving with time. For example, Walther et al [
Much less work has been conducted on negative aspects of design features (
Factors influencing trust judgments with trust or credibility as dependent variable—design features (C=credibility, T=trust, and E=evaluation).
Features | Impact | Factor | Articles using this factor |
Website design features | Positive | Clear layout/design | [ |
Contact details | [ |
||
Authority of owner | [ |
||
Interactive features | [ |
||
Brand/logo | [ |
||
External links | [ |
||
Quality seal/endorsement | [ |
||
Navigation aids | [ |
||
Pictures | [ |
||
Discussion groups | [ |
||
Privacy policy | [ |
||
Identity of sponsor | [ |
||
Health on the Net (HON) network | [ |
||
Personalisation | [ |
||
Functionality | [ |
||
Customer service | [ |
||
Affiliations | [ |
||
Easy to access | [ |
||
FAQ section | [ |
||
Negative | Advertising | [ |
|
Slow | [ |
||
Complex layout/design | [ |
||
Boring layout/design | [ |
||
Inappropriate name | [ |
||
No navigation aids | [ |
||
No/poor search facility | [ |
||
Commercial domain | [ |
||
Uncaring/unconcerned | [ |
||
Textual deficit | [ |
The most widely discussed positive aspect of content features in the literature (
Factors influencing trust judgments with trust or credibility as dependent variable—content features (C=credibility, T=trust, and E=evaluation).
Feature | Impact | Factor | Articles using this factor |
Information content features | Positive | Authority of author | [ |
Credibility/trustworthiness | [ |
||
Objectivity | [ |
||
Ease of use | [ |
||
Readability | [ |
||
Familiarity | [ |
||
Currency (up-to-date) | [ |
||
Triangulation | [ |
||
Usefulness | [ |
||
References | [ |
||
Relevance | [ |
||
Recommended by others | [ |
||
Accuracy | [ |
||
Quality | [ |
||
Clarity/understandability | [ |
||
Adequacy | [ |
||
Quotations | [ |
||
Comprehensiveness | [ |
||
Statistics | [ |
||
Empathy | [ |
||
Negative | Risk | [ |
|
Inappropriate information | [ |
||
Irrelevant information | [ |
||
Complex information | [ |
||
Bias of information | [ |
Readability, familiarity, currency, triangulation, and usefulness are other factors that have fuelled researchers’ interest and which have been the subject of a number of studies. Less common positive content aspects, mentioned only marginally in literature, include the presence of quotations, statistics, and empathy.
The discussion around the negative aspects of the content characteristics of WHI has been much more limited and fragmented. Very few authors have dedicated time to assess what hinders trust (or credibility) in WHI sources. Some researchers have discussed the concept of risk being associated with trust, particularly from a philosophical perspective, stressing that every transaction that requires trust has a degree of associated risk [
Nine articles (
Bates at al [
Factors, alongside trust or credibility (independent variable), influencing online health information seeking.
Outcome variable | Related article | Major findings |
Quality of information | [ |
The quality of health information is dependent on information accuracy and trustworthiness. Quality is then linked to website importance via the number and importance of referral links (ie, links to the website and importance of those websites that link to it) |
[ |
The quality of information is informed by many factors; the first five, in decreasing order of importance, are: accuracy, reliability, credibility, trustworthiness and clarity | |
[ |
Trustworthiness, truthfulness, readability and completeness are the main factors influencing the quality of information | |
[ |
Making a health website more readable improves quality perception of the information, but there is no effect on trust | |
Use of the information | [ |
Trust, together with the importance given to written media, concerns for one’s own health, importance given to the opinion of HCPs and perceived usefulness, is an antecedent of the intention to use the information |
[ |
Perceived benefit, high interactivity and trust positively affect health information use, as well as satisfaction and long-term loyalty | |
[ |
Trust, together with demographics, experience, salience of info and health beliefs, positively influences the intention to use | |
[ |
Older people have concerns about the credibility of online health information and the less they trust it, the less they discuss it with their doctors | |
[ |
Usability and usefulness contribute to trust formation which, in return, is key to return and reuse a source of information | |
Factual list | [ |
College students have ranked a series of criteria to consider when looking for online health information and accuracy, credibility and currency of the information are the top three |
Five articles discuss the factors that affect intention to use health information found online. Lemire et al [
Demographic factors influencing trust formation in Web-based health information seeking.
Factor | Hypothesis | Related articles |
Gender | Women go online/trust online info more than men | [ |
No difference between genders | [ |
|
Education | People with higher education levels go online/trust online info more | [ |
No differences due to education level | [ |
|
Health status | People with poor health go online/trust online info more | [ |
People with good health look for offline health info resources more | [ |
|
People with good health go online/trust online info more | [ |
|
Positive relationship between trust and self-efficacy belief in taking care of one’s health | [ |
|
No differences due to health status | [ |
|
Income | People with higher income go online/trust online info more | [ |
No differences due to income | [ |
|
Age | Younger people (25-55 years) go online/trust online info more | [ |
Younger people (25-55 years) trust online info less than older people | [ |
|
Older people (usually 55+) do not trust online info and prefer offline resources | [ |
|
Articles discussing how young adults (from teenagers to college students) judge and trust online info | [ |
|
Articles discussing how elderly people judge and trust online info | [ |
|
Articles comparing young adults versus elderly online behaviour and trust | [ |
|
Health literacy | High health literacy and seeing HCPs often promote online trust | [ |
No differences due to health literacy | [ |
|
Race | White people go online/trust online info more than black people | [ |
Parental status | Parents, regardless of gender, behave similarly online | [ |
High/low skilled Web users | The higher the skills the lower the trust in the info | [ |
Widely discussed in literature are the two extremes of the age spectrum, the young and the old, and their alleged profound differences in selecting, evaluating, and trusting WHI. Old age has been associated with an overall low trust in Web resources [
Not surprisingly, at the opposite end of the age scale, young adults, in particular teenage users, seem to experience the same lack of judgmental skills of their much older peers when evaluating health information on the Web. In studies conducted on UK and US adolescents, Gray et al [
The intermediate age group, here generally defined as comprising people between 25-55 years, shows an online behavior that is more influenced by other demographic factors, particularly education and income levels. As reported in
The perception of one’s own health status is another determining factor in health information evaluation; however, research has identified conflicting trends. Ye [
A considerable number of the studies reviewed cover the issue of gender, but mostly as part of a larger set of demographic attributes (see
Four articles focused on information sources and trust or credibility. LaValley et al [
Two articles discussed trust from a theoretical perspective. Sillence and Briggs [
This article reports on a systematic literature review of the peer reviewed literature exploring the concept of trust and credibility formation in WHI seeking. The review demonstrates that there is still no consensus of the relationship between the terms “trust” and “credibility”. This review also demonstrates that trust and credibility have been investigated both as the dependent variable, representing the end product of a series of cues and factors influencing the process of information seeking and as independent variable, alongside other variables associated with the quality or use of information. In addition, other research has examined the impact of demographic variables such as gender and age, on trust and credibility judgments in WHI seeking. Nevertheless, while there is a growing body of research in this area, given the importance of the trustworthiness of WHI, there is considerable scope for future research and theoretical development in this area. This includes:
Conceptual or theoretical: It would be of considerable benefit to be able to arrive at a consensus on the relationships between the various variables associated with research into WHI seeking. For example, there needs to be further consideration as to whether trust and credibility or information quality are the most important outcome variables. We propose that consideration of the context may be important in differentiating between trust and credibility, with, for example, trust being the appropriate term to use when information is used to inform a decision or action. This stance would also necessitate the development of an improved understanding of the relationship between trust and risk in digital health information seeking. Having established, or at least, further explored the relationships between trust and credibility, it will be important to increase understanding of the key influencing factors, and the extent to which context might impact on these.
Methods and measurement: Most research on trust and credibility in WHI seeking has adopted a quantitative approach. The purpose of quantitative studies is typically to test theory. However, in the absence of a consensus on definitions of variables and the dominant relationships between them, such studies are unlikely to lead to an integrated and coherent body of knowledge. This is further undermined by the considerable variability in the measurement scales used for trust and credibility and related variables. This needs to be addressed by a much greater number of qualitative studies that offer deeper insights into the context, processes, and judgments associated with WHI seeking and the relationship between these.
Topics: Most studies have investigated the factors that influence trust judgment in relation to WHI in general. Hence, there is scope for more studies that take into consideration judgments on specific health information sources, including specific websites and social media platforms, and the role of the owner and community associated with these platforms in influencing trust judgments. This review has not embraced research on trust regarding health information received in social support groups; this would also be an important agenda for future research. In addition, most prior research has privileged factors that have a positive effect on trust judgments, with few reporting on those factors (such as advertising) that might undermine trust. Finally, the dynamic between trust and risk deserves greater attention, particularly with regard to patients’ perceptions of the seriousness of their complaint.
Impact of demographic variables: There is evidence that various demographic variables (eg, age, income, and gender) may influence WHI-seeking behaviors, but the evidence that this also impacts on their trust judgments is scant. Further research is needed in this area. In particular, the research on disadvantaged groups has focused on identifying their needs, but little work has been done on how these needs and the ability of members of these groups to discriminate between trustworthy and untrustworthy information can be enhanced. In addition, whereas some research has been conducted on the role of gender on trust formation in information seeking, which makes links to the role of the psycho-social context, there is considerable scope for further research into the role of this context in trust formation in health information seeking. Finally, the current research base focuses on health information seekers in the United States, United Kingdom, and Australia. There is a need for research in countries where not only technological differences can play a role in information seeking, but also culture and, more specifically, trust formation and relationships with health organizations and professionals are likely to differ from non-western countries.
health care professional
Web-based health information
None declared.