A systematic literature review of attitudes towards secondary use and sharing of health administrative and clinical trial data: a focus on consent

Qualitative research methodologies included interviews (face-to-face or via telephone) [16, 19, 22, 45] and focus groups [31, 33, 36, 38], a combination of both [49] or surveys and focus groups [57]. Other methodologies included questionnaire-based interviews [50], surveys [15, 17, 18, 20, 21, 25, 26, 28‐30, 32, 34, 37, 39, 40, 42, 44, 46, 48, 53‐55, 58, 59] and combinations of deliberative sessions/interviews and surveys [23‐25, 27, 56, 57]. Two studies used a citizens’ jury model [43, 51], one study was a randomised controlled trial [47], one was a nested cohort within a randomised controlled study [41], three studies requested consent to access data by letter [35, 52, 61] and one requested consent directly from the participant [60]. Studies were conducted in several countries; a breakdown by country is presented in Table 3.

Most articles focused on the attitudes of the general public towards the access to and secondary use of digital health data in different settings, particularly general medicine [16, 18, 20, 21, 26, 30, 31, 34‐38, 40, 41, 44‐48, 50‐56, 58‐61], but also National Cancer databases [19, 39], and pharmacoepidemiological [43] and epidemiological [29, 33, 49] research. Other studies focused on the attitudes of health consumers to secondary data analysis and sharing of health data in individuals: attending US Veterans Affairs (VA) facilities [27], retirees [45], recently discharged from tertiary care [23], patients attending a hospital with a cancer diagnosis [32], cardiology patients [15] and patients with asthma and stable angina [17]. Other articles focused on responses from those with acquired immune deficiency syndrome (AIDS) or multiple sclerosis (MS) or mental health concerns [42], rare diseases [25, 28], clinical trial data [22], fertility [24] and respondents with potentially stigmatising conditions (DM, hypertension, chronic depression, human immunodeficiency virus [HIV], breast cancer or lung cancer) [57].

Articles considered general attitudes towards health data use [15‐18, 20, 21, 25, 26, 37, 38, 41, 45‐48, 50, 57‐59, 61], linking health administrative data to clinical trial data [32] and reuse of clinical trial data [22], access to medical records [23, 27, 29, 31, 33, 35, 40, 42‐44, 48, 51, 52, 54‐58, 60], statistical databases [36], registries [19, 24, 28, 30, 39], health data for epidemiological research [49] and the linking of health insurance data with survey data [34]. Commercial access to health data [53] was considered in one article. Five studies included data from respondents both over and under the age of 18 years of age [16, 19, 26, 37, 60]; where this has happened, only data from respondents over 18 years of age have been included in this analysis.

Several mechanisms of consent were discussed in the articles; a description of each of the consent mechanisms, by study, is included in Table 4.

Results of the quality assessment are provided in Table 2. QualSyst [12] scores ranged from 0.35 to 1.0 (possible range 0.0 to 1.0). While no studies were blinded, most provided clear information on respondent selection and data analysis methods and used justifiable study designs and methodologies. No key themes stood out for studies which were deemed to be of lower quality. No data were from randomised studies; the highest level of evidence was from a nested cohort, with other data obtained from studies which used surveys and interviews.

Five studies described the issues of data usage and consent preferences of Continental European respondents [22, 25, 28, 30, 50] representing a total of 6790 respondents. Consent preferences for accessing data held in registries were not universal, and a willingness to share health data was not precluded by a wish to control access to it [25]. In the setting of registry-based research, respondents to a quantitative study were divided between believing that a single informed consent was acceptable, that no consent was necessary, that consent should be sought in some cases or sought every time [30]. Some respondents believed that their data should not be used at all for research, while others believed that everyone’s medical records should be available for research [30]. Where there is a potential for the data to be used for research, respondents wanted to be informed at the time of hospital admission, and over half of respondents wanted specific details about the type of research for which it could be used [30]. In the setting of a leukodystrophy registry, respondents in a qualitative study believed that a combination of initial broad consent, supported by ongoing information about the use of data, research results and new partnerships (academic and/or pharmaceutical companies) was acceptable [28]. The use of an interactive consent tool, where individuals could specify their consent preferences and exercise more control over their data, was supported [22].

Sixteen studies [16, 19, 23, 24, 26, 29, 31, 33, 37, 39, 44, 46, 47, 51‐53] from the UK and Ireland discussed health data usage and consent preferences representing a total of 108,824 respondents. The proportion of respondents who would give permission to access information in their medical notes was high, but varied based on the type of information to be used [23]. Most respondents wanted to be asked when data relating to side effects and medical history were taken from medical records, while few wanted to be informed when data on sex and age were sought (5% and 7% respectively) [23]. Signing a consent form to allow future data use during the patient’s hospitalisation was a preferred method but respondents were also happy to be informed, but not required to provide consent, each time the data was to be used [23]. Variation in views on the need for consent was seen in other studies; while some respondents acknowledged that re-consent is difficult and has the potential for low response rates, they still saw it as best practice to ask [33]. For some, an opt-out consent process was seen as acceptable as it allows the individual the right to refuse participation while informing them of the types of research being undertaken [33, 51, 52]. Higher rates of support were shown for the current data collection methods used for the UK cancer registry in people living with cancer (PLWC) (65%) compared with general public respondents (52%); however, 9% (PLWC) and 12% (general public) were opposed [39]. Of those who were opposed, 6% (PLWC) and 17% (general public) believed that it should be an ‘opt-in’ process rather than ‘opt-out’ [39]. While there are opt-out and data withdrawal options for the UK cancer registry, few were aware of these options [39]. Two studies noted the complexity of retrospectively opting out of data collection processes [24, 31]. A citizens’ jury process found that respondents preferred opt-out consent over opt-in (70.6% vs 17.6%); a small percentage (8.8%) believed that all records should be available for use for the public benefit [51]. In one study, younger respondents equated an ‘opt-in’ process with being asked if their data could be used [16].

Ten studies from the USA [17, 18, 20, 27, 35, 38, 40, 45, 58, 60] and six from Canada [15, 32, 42, 55‐57] discussed secondary data use and consent preferences representing a total of 42,620 respondents. Studies from Canada showed variability in consent preferences and included the use of consent each time, broad consent, and notification with opt-out consent [55]. Many respondents believed that no consent or notification was required in some circumstances [42, 55]. Where general consent was provided, 80% wanted to periodically review this decision, while others wanted either no or minimal involvement (36%) or notification with an opt-out option (24%) [55]. Various consent processes were proposed across the studies and included opt-out [27], opt-in [56], opt-in/one-off consent with blanket authorisation [27, 42], consent to be sought each time [27, 42, 56], assumed consent [56] or no requirement for consent but with individuals being informed about data usage [42]. Respondents liked different aspects of each consent process [56]. For some, where consent was not sought, respondents considered it to be a violation of privacy [38]. In the setting of potentially stigmatising health conditions, respondents to a mixed-methods study had a range of views about consent ranging from ‘just use it’ to ‘the information should not be shared at all’ [57]. Respondents felt that where data were to be used for quality improvement, no consent was needed; however, where data were to be linked or used in profit-based activities, consent was required before each use [57].

Six studies from Australia [21, 36, 48, 49, 59, 61] and two from New Zealand [43, 54] discussed consent preferences and represented a total of 42,104 respondents. While seeking consent to use data should be the ‘cornerstone’ of contemporary research practice [49], views on consent about the use of health data for research ranged from not important to the need to provide detailed information [36]. Respondents to a qualitative study believed that while people had the right to refuse access to health data for research, most believed that data linkage research could be undertaken without consent [59]. Reasons for not requiring consent included a perceived benefit from research, large datasets serving as protection, practical considerations, that the use of de-identified data does not breach privacy, and that audit activities do not require consent [59]. Where data was to be used for epidemiological research, respondents in a mixed-methods study were divided about the requirement for consent [49]. Opt-out consent was considered acceptable to 54% of the respondents in one study, but nearly one-third (28%) preferred an opt-in method and a fifth had no preference (19%) [21]. The use of a hybrid consent model was proposed in a quantitative study from New Zealand [54]. This method proposed a mix of general consent processes including specific criteria for use in the context of accessing data in the clinical setting and the requirement for specific consent when data is accessed for other purposes [54].

Several other themes were addressed in the included papers and are presented below by theme.

Several studies found differences in attitudes towards consent by respondent age [17, 30, 52]. Across the studies, older respondents were more willing to share or link data than younger participants [20, 32, 46] and those with younger respondents were more willing to consent to health data use [25, 35, 37, 58, 61] and/or record linkage [26, 34]. One study found that while patterns of consent were similar across responders, consent decreased with age (over 50 years of age) in both males and females [29].

Differences were seen in support for data reuse and methods of appropriate consent processes by sex; however, these were not always significant [26, 30, 46, 52]. Where it was a factor, males were more likely to consent to medical record review [29] and believed that informed consent was not required for registry-based research more than women [30]. Women believed that consent should be required in some cases more than males (44% compared with 31%) [30], were less likely to give authorisation [35], and consented less [58] suggesting a greater desire for control over their data [25] compared with males.

By location, respondents from Northern Ireland (adjusted OR 50.56; 95% CI, 0.50–0.63) had lower levels of support for data access compared with respondents from other parts of the UK (adjusted OR 51.17; 95% CI, 1.06–1.29) (N = 50,994) [26], and respondents from the former West Germany were less likely to consent to data linkage compared with those from Berlin or East Germany [50]. Respondents living closer to a study centre (5.8% and 2.1%) had higher rates of refusal compared with those living further away [35].

Levels of education influenced attitudes towards consent. Respondents with a secondary education were more likely to provide consent compared with those with lower levels of education [25, 26, 37, 45, 46, 50, 58, 61]. Education level also impacted a respondent’s willingness to share health data without consent. Those with no academic qualifications were less likely to agree to research on health data being conducted without consent compared with those with higher levels of education (38%, no qualification; 26%, graduate level), with this decreasing with as the respondents’ level of education increased [44]. Those with lower levels of education and who had lower incomes were less likely to be non-responders to requests for consent compared with respondents who actively declined consent [58]. In one study, respondents who were married, illiterate, who lived in a suburban area (compared with urban/rural) or those with a lower monthly income were less likely to consent to data linkage [34]. Three studies noted the impact of socio-economic variables on consent; however, all reported different outcomes. While one study found that socio-economics did not influence consent [37], other studies found that low income did influence consent patterns [34] and that respondents in the higher socio-economic group were less likely to provide consent when compared with those in lower socio-economic groups [24]. Respondents who declined to answer questions about income from investments had lower levels of consent for data linkage, however other socio-economic variables did not appear to influence consent [46]. Those who provide consent were more likely to have health insurance [61]. Other influences on providing consent for data use included undertaking voluntary work or previous data record linkage by a family member [46].

Differences in consent preferences were noted by respondent ethnicity. Research from a study in the UK found that consent for data linkage was significantly lower (58.9%) in respondents (N = 50,994) who identified as non-white compared with those who identified as white (72%) [26]. This was similar to two other studies from the UK and the USA where those who reported their ethnicity to be British/Irish white had higher consent compared with other groups [37], and those who identified as being of African-American heritage were less likely to consent to data usage [58]. Language and the need for an interpreter were also seen to influence consent. In an Australian study, opt-out consent was preferred by respondents who were illiterate in their primary language or who were refugees [21] while an English study found language to be a barrier to discussing/seeking consent [24].

Consent preferences were found to be influenced by the respondent’s health status. Respondents with lower physical and mental functioning scores, measured using the 36 Item short form (SF-36) questionnaire, were shown to have lower levels of consent for data usage [34]; however, in a second study, respondents with lower SF-36 physical and mental health scores were more likely to consent [58]. In one quantitative study, respondents with lower Charlson Comorbidity Index (CCI) scores were less likely to allow survey and health data linkage compared with respondents with higher scores [20]. Experience of a major personal illness and hospitalisation in the last year [61] and severity of illness [58] did not impact the frequency of consent; however, respondents with more severe rare diseases were more likely to support data sharing compared with those with less severe diseases [25]. Consent was higher in respondents with life-limiting and lifelong illness [26], those with health conditions under investigation [29], those with two or more medical diseases [50], those in good health (compared with those in poorer health) [30], and those with diabetes or who were obese [37]. In contrast, in one quantitative study respondents with long-term health conditions were more likely to be against health data sharing compared with those with no long-term health conditions (~ 25% vs 20%) [44]. Respondents (N = 15,997) who presented for mental health concerns, trauma, and eye care had higher rates of refusal for providing access to medical records for research [60].

Several health topics were considered more sensitive than others and influenced consent preferences [48]; the need for ethical oversight when research is undertaken on a sensitive topic [30] was noted. Respondents were less likely to provide consent to access medical records for research which included sensitive topics [35]. Requesting data on sexual orientation [23], sexual or sexually transmissible diseases [42], infectious diseases [35], reproductive issues [35], contraception or female genital disorders [58], urinary disorders [58], mental health [25, 35, 42], disability [25] and genetics [25] were all reasons for increased need to ask permission or provide consent to access data or were associated with lower levels of consent. Interestingly, in one study non-consent rates were higher in respondents seeking care for uncomplicated diabetes and or headache [58], conditions which may not be considered sensitive by healthcare consumers. Women receiving pregnancy care had the highest response of ‘undecided’ about providing consent [60]. In the setting of potentially stigmatising conditions (HIV, chronic depression, HT, alcoholism, DM, breast or lung cancer), provision of consent was similar between diseases [57]. The diagnosis of stable angina or asthma was not considered particularly sensitive [17]; however, for others, information about symptoms and the name of their disease [25] was. Consent was lower in respondents who did not answer questions on smoking status, income, or functional status [58], however, questions relating to income did not always decrease consent [47]. Respondents to a study from New Zealand were less willing to share data of a sensitive nature with those not involved in their care [54]. In one study, respondents with HIV, MS or mental health presentations believed that only physicians involved in their care should be able to access medical records without consent [42]. Where data was to be linked, respondents in one study were unable to reach a consensus on consent when medical data were to be linked with data on teenage pregnancy and state benefits, birthweight and future health outcomes, mental health and criminal records, and asthma diagnosis and postcodes [16]. In other studies, some respondents identified the need for consent where health, employment and WorkCover (workers compensation insurance) data [59] were linked. Consent was not required when health data were linked to cancer registry and death data, and if de-identified health data and criminal records [59].

Several articles discuss the relationship between trust, transparency, privacy and consent, and quality, and these issues are explored at length in a subsequent publication [9]. Other influences on consent included health literacy and government insurance status [18], or requesting a national identity number [41]. Other negative influences on consent included a fear of discrimination, fraud, threat to personal safety and use of data without their knowledge or in a context they do not approve of [25]. Further, perceived benefits and harms, trust, anxiety or feelings of being overwhelmed, and understanding of processes and research more generally influenced consent [24]. Where data were to be used in a for-profit setting or where individuals were more concerned about privacy [57] and where information was to be shared with a third party [25] respondents required more conditions and more restrictive consent processes. Interestingly, in a Canadian study, there was a difference in consent rates for the use of paper-based versus electronic records, with 27% percent of respondents (N = 1,235) believing that electronic data can be used without permission compared with 12% for paper records [55]. Respondents who responded to the request for consent via a website were younger compared with those who responded by letter (38.7 years compared with 53.5 years) [52].

The role of human research ethics committees (HREC) and institutional review boards (IRBs) in influencing the need for consent was noted in one study [40]. In one article, the requirements of the IRB were shown to have significantly impacted the overall rates of study consent and completion [40]. Three studies [25, 27, 42] described respondents’ views about the role of HRECs in deciding if researchers should be allowed to access existing health data for research (secondary data analysis). Even in the setting of HREC approval and where the research was deemed low harm, 67.7% of respondents (N = 235) wanted to be asked to consent to the use of their data for medical research [42]. This was similar to a European study, where near equal numbers of respondents (N = 2,013) were for (49%) and against (43%) allowing an HREC to decide about access to data [25]. Finally, one study found that a third of respondents believed that the decision of the HREC regarding consent was sufficient, although two-thirds of respondents wanted to be able to tell the HREC how they wanted their data shared [27].