Abstract
Greater attention is being focused on the willingness and motivations of potential subjects who are recruited for research protocols. Given the importance of subjects' abilities to choose freely and reason through their decisions about entering psychiatric research, empirical researchers have been developing assessment and education tools that address the potential vulnerabilities of research subjects. In this study subjects' responses and reasons for or against participation were elicited as part of an assessment of their research decision making. Fifty-two persons diagnosed with a thought disorder were asked to consider a hypothetical research study using the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR). Their responses were documented, coded for content, and correlated with demographic characteristics and scores on scales rating psychosis, cognition, and health-related quality of life. Subjects expressed common considerations that have been identified by other psychiatric investigators, as well as by those studying nonpsychiatric protocols. In general, reasons were both appropriate to the study being considered and appropriately linked to common considerations that flowed logically from the study. However, elements of the therapeutic misconception were evident as well. Willingness to participate was correlated with higher MacCAT-CR scores on certain scales, better education, and lower levels of psychosis and cognitive impairment. These findings highlight both the strengths and weaknesses of the decision making of research subjects with thought disorder. Research protections and assessments may consequently be appropriately targeted to specific vulnerabilities. Because of differences in severity of illness, cognition, and reasoning among subjects who decline to participate in research, greater attention to this population appears warranted.
Keywords: research ethics, informed consent, research participation
Introduction
The motivations of subjects who enter psychiatric research have gained increasing attention over the past few years,1–4 in large part because of concern about the vulnerabilities of subjects with psychiatric disorders. A previous line of research on decision-making capacity and informed consent has now been expanded to include new conceptualizations of voluntarism that focus on motivational issues.5 The abilities to reason and choose freely to participate in research remain particularly important in psychiatric and behavioral research because the disorders of interest frequently affect the cognitive processes, reasons, and choices of participants.6
The few studies that have examined this issue suggest that the motives individuals have for participating in psychiatric research may be more closely associated with rational reasons such as altruism than with irrational impulses driven by psychiatric symptomatology.1,2 But other investigators working with both psychiatric and nonpsychiatric subject populations have suggested that mistaken notions of self-interest (often termed “therapeutic misconception”) may influence research participation.7–9 Given the paucity of data and the uncertainty about subjects' motivations, it is critical to identify variables related to willingness to participate that may be markers of vulnerability. These can alert researchers and surrogates to those groups that may require greater protection while allaying concerns about others that do not.
Based on the previous literature,1–9 we hypothesized that patients with thought disorders such as schizophrenia would be more willing to participate in research if they were better educated, had higher decision-making scores as measured by the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), and higher scores on a cognitive capacity screen. We hypothesized that their motives for their decisions would be largely rational. Length of illness, view of prognosis, and prior participation were also anticipated to influence research participation. We predicted that factors like ethnicity and sex would not influence participation decisions.
METHOD
Subjects
Subjects for this study were recruited from 3 sites: 45 stable patients from 2 Massachusetts state hospitals and 7 outpatients from another site. Massachusetts state hospitals serve seriously and persistently ill patients, who had an average length of stay of 353 days during the years of subject recruitment. Subjects were approached through their physicians, who identified them as thought-disordered and capable of completing a 45-minute interview, or responded to announcements at community meetings. Patients approached by their own physicians were clearly instructed that they could refuse and that refusal would not affect their care. Refusal rates and debriefing suggested strongly that subjects were not unduly influenced. Subjects were informed that a number of questionnaires would be administered after discussion of a hypothetical drug trial and that they would be paid $10 for their participation. All provided written informed consent. The study was approved by both university and Department of Mental Health institutional review boards.
All 52 subjects met DSM IV-R diagnostic criteria for either schizophrenia or schizoaffective disorder by clinical interview and/or chart review. The diagnoses of inpatient subjects who were not known to the first author were confirmed with treating psychiatrists and clinical teams. Diagnoses of outpatient subjects were confirmed by accompanying family members or clinicians present who knew the subjects. Demographic information is presented in Table 1.
Table 1.
Demographics of Subjects With Thought Disorder According to Willingness to Participate in Research
| Total (N = 52) | Willing to Participate (n = 33) | Unwilling to Participate (n = 19) | Test of Difference | Significance | |
| Male | 76.9% (n = 40) | 72.7% (n = 24) | 84.2% (n = 16) | Fisher's Exact | 0.50 |
| Age in years | M = 37.39 | M = 38.18 | M = 37.11 | t(50) = −0.32 | 0.75 |
| (SD = 11.67) | (SD = 11.93) | (SD = 11.51) | |||
| Race | |||||
| White | 80.8% (n = 42) | 81.8% (n = 27) | 78.9% (n = 15) | Fisher's exact | 1.00 |
| Education | |||||
| High school graduate or less | 49.0% (n = 25) | 36.4% (n = 12) | 72.2% (n = 13) | Fisher's exact | 0.02 |
| More than high school | 51.0% (n = 26) | 65.6% (21) | 27.8% (5) | ||
| Number years had diseasea | M = 20.37 (SD = 28.56) | M = 21.63 (SD = 34.73) | M = 18.06 (SD = 10.94) | t(49) = −0.42 | 0.67 |
| Perceived disease progressb | |||||
| Worse | 3.9% (n = 2) | 3.1% (n = 1) | 5.3% (n = 1) | χ2(2) = 0.82 | 0.66 |
| Stable | 70.6% (n = 36) | 75.0% (n = 24) | 63.2% (n = 12) | ||
| Better | 25.5% (n = 13) | 21.9% (n = 7) | 31.6% (n = 6) | ||
| Expectation of condition in 6 monthsb | |||||
| Worse | 5.9% (n = 3) | 9.4% (n = 3) | 0% (n = 0) | χ2(2) = 1.98 | 0.37 |
| Stable | 47.1% (n = 24) | 46.9% (n = 15) | 47.4% (n = 9) | ||
| Better | 47.1% (n = 24) | 43.8% (n = 14) | 52.6% (n = 10) | ||
| Expectation of condition in 1 yearc | |||||
| Worse | 2.0% (n = 1) | 3.2% (n = 1) | 0% (n = 0) | χ2(2) = 3.07 | 0.22 |
| Stable | 46.9% (n = 23) | 54.8% (n = 17) | 33.3% (n = 6) | ||
| Better | 51.0% (n = 25) | 41.9% (n = 13) | 66.7% (n = 12) | ||
| Expectation of condition in 5 yearsd | |||||
| Worse | 13.9% (n = 5) | 13.8% (n = 4) | 5.9% (n = 1) | χ2(2) = 0.94 | 0.62 |
| Stable | 44.4% (n = 16) | 31.0% (n = 9) | 41.2% (n = 7) | ||
| Better | 69.4% (n = 25) | 55.2% (n = 16) | 52.9% (n = 9) | ||
| Participated in research beforeb | 39.2% (n = 20) | 43.8% (n = 14) | 31.6% (n = 6) | Fisher's exact | 0.55 |
| Outpatient | 13.5% (7) | 85.7% (6) | 5.3% (1) | Fisher's exact | .24 |
| Inpatient | 86.5% (45) | 60.0% (27) | 40.0% (18) |
M = mean; SD = standard deviation
N = 33 for Willing to Participate and n = 18 for Unwilling to Participate.
N = 32 for Willing to Participate and n = 19 for Unwilling to Participate.
N = 31 for Willing to Participate and n = 18 for Unwilling to Participate.
N = 29 for Willing to Participate and n = 17 for Unwilling to Participate.
Measures
All subjects received the MacCAT-CR, an instrument designed to assess decision-making capacity and adapted to the elements of a specific research protocol.10 MacCAT-CR administration involves disclosure of information about the study that subjects are being asked to consider, in this case a hypothetical medication trial, followed by questions that assess understanding, appreciation, reasoning, and choice. The hypothetical trial, designed for outpatients, involved random, blinded exposure to a new antibiotic for sore throat versus an established treatment; risks included those of blood draw and non-life-threatening side effects of the drug. The inability to guarantee direct benefit was explained as well. An antibiotic trial was chosen so that any prior knowledge of psychiatric research would not contaminate subjects' understanding of the protocol. It followed the design of mainstream protocols identified by colleagues who conduct antibiotic research.
Specific rules for follow-up probing were developed. Interviewers were allowed to use up to 5 probes for each question, which involved repeating language from established MacCAT probes or feeding back the subjects' responses when answers were unclear. A repeated disclosure was permitted in the appreciation subsection when subjects did not recall the study's lack of primary benefit to the subject. This probing strategy was designed to maximize subject performance.
The first author (PC) conducted 45 of the assessments and trained the second author (CG) in use of the instrument. After observation of 2 interviews, the second author interviewed 4 subjects with the first author present, the surveys were scored independently, and any differences were discussed. Interrater reliability scores were derived from 8 interviews, the 4 interviewed by the second author and scored independently by the 2 raters and audiotapes of 4 later interviews by the first author.
Raters agreed 75% of the time (6 out of 8 interviews) on the MacCAT-CR Appreciation subscale ratings (scored 0–6 points), with both disagreements differing by 1 point. Raters agreed on 5 of 8 ratings on the Reasoning subscale (scored 0–8 points), for a 62.5% agreement rate, with all 3 scores differing only by 1 point. The 2 raters also agreed on 5 of the 8 scores on the Understanding subscale (scored 0–26 points), a 62.5% agreement rate, with 2 of the disagreements differing by 1 point, and the third differing by 2 points. Raters agreed on 7 of the 8 ratings on the Choice subscale (scored 0–2), for an 87.5% agreement rate, with the 1 disagreement differing by 1 point. Therefore, in this study there appears to be adequate interrater reliability on the subscales of the MacCAT-CR.
Subjects also completed the SF-36 (Short Form-36) health-related quality-of-life instrument,11 the MMSE (Mini-Mental State Examination),12 PANSS (Positive and Negative Syndrome Scale),13 and a background information form asking about length of illness and view of prognosis. These instruments were completed at the same encounter as the capacity assessment, in the same order for all subjects, and by the same unblinded interviewer.
Subjects' willingness to participate in the hypothetical drug trial was elicited from responses to the MacCAT-CR Communicating a Choice subsection (“Now that you have had some more time to think it over, I would like to ask you again whether you think you are more likely to say ‘yes’ or ‘no’ if you were asked to be in this study.”). Responses to questions in the Reasoning subsection (“So you think you would choose to be/not to be in the study. What makes this the best choice for you?”) were coded for content.
Statistical analyses were conducted using SPSS Version 13.0. Differences between groups on categorical data were analyzed using chi-square tests or Fisher's exact probability test. Differences between groups on ordinal or continuous data were analyzed using t-tests.
Results
Subject Demographics
Fifty-two subjects diagnosed with schizophrenia or schizoaffective disorder between the ages of 19 and 59 completed the interview (Table 1). Twenty-three others refused. Three-fourths (76.9%) of the subjects were male. The majority (80.8%) were white, 9.6% were African American, 7.7% Hispanic, and 1.9% Native American. One-third (33.3%) had less than a high school degree, 15.7% had a high school degree, 35.3% had technical training beyond high school or some college but no degree, and 15.7% were college graduates.
Subject Characteristics Correlated With Willingness to Participate in Research
When asked whether they would choose to take part in the research, 33 (63.5%) subjects said “yes,” and 19 (36.5%) said “no.” These groups were examined for significant differences (Table 1).
The two groups did not differ by gender, with 60.0% of the men and 75.0% of the women agreeing to participate. Nor did the groups differ in age or race. The more education a subject had, the more likely he or she was to indicate willingness to take part in the research.
Willingness to participate in research was not significantly associated with any of the SF-36 scales, the number of years a subject had the disease, the perceived progression of the disease at the time, or anticipated prognosis within 6 months, 1 year, or 5 years. Nor was it associated with previous participation in research. Outpatients did not differ from stable inpatients in their willingness to participate, and excluding the outpatient group from the analysis did not result in any statistically significant changes in the correlations except for a single scale on the SF-36 (emotional role, M = 57.69, SD = 37.19 for those willing to participate vs M = 33.33, SD = 38.49, for those unwilling, t(40) = −2.03, p = .05).
Reasons for Participation in Research
The first three responses to the Reasoning subscale of the MacCAT-CR were grouped according to similarity, resulting in 6 general domains of responses: money/desire for payment for participation; identification of general and specific risks attached to research; general aversion to research and its procedures; reasons related to receiving treatment (including better treatment); altruism; or other (psychotic) reasons (see Table 2).
Table 2.
First Three Reasons Given for Willingness or Unwillingness to Participate by Willingness to Participatea
| Reason | Willing to Participate (n) | Unwilling to Participate (n) | χ2 | p |
| Money | 7.7% (2) | 6.7% (1) | Fisher's exact | 1.00 |
| It is a risk | 55.2% (16) | 75.0% (12) | Fisher's exact | 0.22 |
| Don't like research | 3.8% (1) | 66.7% (12) | Fisher's exact | < 0.001 |
| Treatment-related benefits | 50.0% (15) | 26.7% (4) | Fisher's exact | 0.20 |
| Altruism | 82.8% (24) | 25.0% (4) | Fisher's exact | < 0.001 |
| Other (psychotic) response | 0% (0) | 5.3% (1) | —b | — |
Not everyone gave a third reason. The percentages for answers and the chi-square test of the differences in answers are based on those who did, 26 of those willing to participate and 15 of those unwilling to participate. The percentages for “No third reason given” are based on the full sample of 33 willing to participate and 19 unwilling to participate.
N too small to conduct a statistical test.
Many subjects were generally unwilling to “take a chance” in the research protocol; others eschewed the specific risks of a new medicine or uncertain side effects. Conversely, some who were willing to participate explained that they had experienced similar risks before (eg, with new medication) or were willing to take a risk for the purposes of the study. Those who expressed altruism were interested in “helping people in general,” helping “science” or “medicine,” helping “find a better treatment,” or helping “learn something.”
Subjects who expressed an aversion to the research expressed reasons such as not wishing to be treated like “guinea pigs,” not “liking” research, or not knowing or controlling the choice or dose of their medication (fixed elements of the study).
A number of subjects reported they might or would “get something better” if they participated in the research or would “get a better treatment” (some without considering the alternative of not getting a better treatment). Some who expressed treatment-related reasons said they would participate because they trusted their doctor (who was not involved in the conduct of the hypothetical study). Of the 52 subjects, 12 reported reasons that were both altruistic and personally motivated (eg, to help others and to receive payment or receive a new treatment).
Of the reasons offered, willing and unwilling subject groups differed significantly on 2 of them (Table 2). An aversion to research was more likely to be mentioned by those who were unwilling to participate (66.7% vs 3.8%, Fisher's exact p < .001), and altruistic considerations were more likely to be mentioned by those who were willing to participate (82.8% vs 25.0%, Fisher's exact p < .001).
MacCAT-CR Scores
Subjects who were willing to participate scored higher on 2 MacCAT-CR subscales, Understanding and Expressing a Choice, but not on the 2 other MacCAT-CR subscales, Appreciation and Reasoning (see Table 3), although the differences between the groups on the latter two scales were in the same direction and approached statistical significance.
Table 3.
MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) Subscale Scores and Mini-Mental State Examination (MMSE) Scores of Subjects According to Willingness to Participate in Research
| Willing to Participate M (SD) | Unwilling to Participate M (SD) | Test of Difference | Significance | |
| Understandinga | 24.15 (3.52) | 19.42 (8.13) | t(21.95) = −2.41 | 0.025 |
| Appreciationa | 4.76 (1.60) | 3.63 (2.22) | t(28.97) = −1.94 | 0.06 |
| Reasoninga | 6.97 (1.79) | 5.68 (2.87) | t(26.27) = −1.76 | 0.09 |
| Express a Choice | ||||
| 2 | 97% (32) | 73.7% (14) | χ2(2) = 7.12 | 0.03 |
| 1 | 0% (0) | 15.8% (3) | ||
| 0 | 3% (1) | 10.5% (2) | ||
| MMSEb | 28.30 (2.07) | 25.78 (3.46) | t(25.18) = −2.78 | 0.01 |
M = mean; SD = standard deviation
N = 33 for Willing to Participate and n = 19 for Unwilling to Participate.
N = 27 for Willing to Participate and n = 18 for Unwilling to Participate.
MMSE and PANSS
Subjects who were willing to participate scored significantly higher on the MMSE (Table 3) and significantly lower on their total PANSS scores, indicating less psychosis (Table 4). They also scored significantly lower on the extensive PANSS General Symptoms scale but not on any of the other PANSS subscales.
Table 4.
PANSS Scores of Subjects According to Willingness to Participate in Research
| Willing to Participate (n = 27) M (SD) | Unwilling to Participate (n = 18) M (SD) | Test of Difference | Significance | |
| Positive symptoms | 15.33 (4.59) | 16.44 (4.40) | t(43) = 0.81 | 0.42 |
| Negative symptoms | 16.85 (5.29) | 21.17 (9.28) | t(24.41) = 1.99 | 0.09 |
| General symptoms | 28.30 (5.55) | 33.11 (7.87) | t(43) = 2.41 | 0.02 |
| Composite | −1.51 (7.12) | −4.72 (9.29) | t(43) = −1.31 | 0.20 |
| Anergia | 8.33 (3.78) | 10.72 (5.32) | t(43) = 1.76 | 0.09 |
| Thought disorder | 8.96 (3.39) | 10.33 (3.56) | t(43) = 1.30 | 0.20 |
| Activation | 4.52 (1.74) | 4.89 (1.45) | t(43) = 0.75 | 0.46 |
| Paranoia | 5.74 (2.41) | 5.05 (1.70) | t(43) = −1.04 | 0.30 |
| Depression | 7.30 (3.11) | 6.56 (2.33) | t(43) = −0.86 | 0.39 |
| Total | 60.48 (10.11) | 70.72 (18.67) | t(43) = 2.37 | 0.02 |
M = mean; SD = standard deviation
Discussion
In this study subjects diagnosed with schizophrenia or schizoaffective disorder were more willing to participate in a hypothetical research protocol if they scored better on the MMSE and PANSS, scored higher on certain MacCAT-CR subscales, and if they were better educated. Whether they were willing to participate in the study or not, subjects almost always offered reasons that were appropriate to the study being considered and that resemble reasons given by non–mentally ill persons in comparable studies.14–17 Given that subjects were considering a non-life-threatening hypothetical antibiotic protocol, it will be important to replicate these findings with subjects who face the proximity and rigors of actual psychiatric studies and among those who are considering protocols with different risk-benefit profiles.
As has been true in studies of nonpsychiatric populations, however, some subjects offered reasons for participation that reflected unreasonable beliefs about the likelihood or degree of benefit that they would experience, ie, elements of the therapeutic misconception.9 Although some subjects responded appropriately that they “might” receive an improved medication in the hypothetical study, others did not express such answers with the uncertainty appropriate to research. These respondents stated simply that they would “get better” or “get a better treatment.” That some subjects expressed trust in their own doctor, who was not involved in the research study, as a basis for participation also suggests misunderstanding of the research process. Some subjects expressed reasons that were both altruistic and personally motivated, suggesting that subjects could hold competing motivations at the same time; this is a finding that has been noted repeatedly in studies of therapeutic misconception and that reflects the complexity of ascertaining subjects' appreciation of the research setting. Nonetheless, unreasonable hopes for direct benefit and the failure to recognize that research is primarily geared toward the acquisition of new knowledge remain important issues in this study, as in those from other areas of medicine.9,15,17
Although both those who were willing and unwilling to enter research offered reasons related to risk to justify their decisions, the differences between them, as might be expected, appeared most strongly in considerations of altruism and aversion to research. Those who were willing to participate were more heavily altruistic, while those who declined were more hostile to research in general. Those unwilling to participate were more likely to dislike research and its procedures (eg, being “treated like a guinea pig;” not being able to choose the medication or dose). Despite the distaste expressed for the protocol, these reasons indicated a good understanding of the purposes and procedures of the research study being considered. Further research may be useful to assess whether these reasons correlate with changes in the level of research risk. It may be helpful to investigate, for example, whether those who express altruism are more likely to take on research of greater risk and lesser benefit, or whether those who decline the risks of research do so without these considerations.
Associations of willingness to participate with decision-making capacity included higher MacCAT-CR Understanding scores, underscoring the importance of robust consent procedures. If better understanding of research procedures leads to greater willingness to participate, as these data suggest, empirical research is offering yet more support for the informed consent process and the movement toward enhanced consent procedures.18–20 Higher MacCAT-CR Choice scores suggest the greater capacity of those who were willing to participate to express a stable choice during the interview. Those unwilling to participate were more likely to demonstrate a vacillating or uncertain choice by the conclusion of the interview (hence lower subscale scores). This may raise researchers' sensitivity to thought-disordered subjects who express ambivalence or uncertainty at the conclusion of consent procedures.
Although Appreciation and Reasoning subscales did not differ significantly between the 2 groups, the differences trended toward statistical significance. A larger sample would provide more power to explore this possibility. If, as we suspect, capacities to appreciate and reason also contribute to research participation, greater efforts to assess and educate subjects in these areas (including on appreciation elements such as the therapeutic misconception) will improve the quality of informed consent. The rates of research participation among those with a weakly defined or poorly reasoned antipathy to research may also be improved. If willingness is indeed correlated with better decision-making scores, the correlation with more education is not surprising given prior reports of correlations between this variable and better performance on the MacCAT instrument.
The correlations between willingness to participate and better symptom control and cognitive capacity are still being established in the psychiatric literature. Stanley et al.21 described no correlation of psychopathology with willingness to participate, although recent efforts seem to suggest that subjects with less psychosis and less cognitive impairment will be better able to understand research protocols and more likely to volunteer their participation.1–4 Although the MMSE alone is not an ideal determinant of cognitive capacity, it is an adequate screen, and it has been used broadly enough in past research to provide a standard for comparing groups of subjects. Our findings underscore the need to investigate the differences between more willing and intact research participants and more impaired individuals who may refuse participation. Different recruitment and education strategies may improve and broaden research participation.
Overall, this study offers further data to support greater care in the recruitment of research subjects with higher levels of psychosis and cognitive impairment, lower levels of education, and less understanding of research disclosures. Research protections and capacity assessments may be more appropriately targeted to subjects with these vulnerabilities. Data are also available to support both altruistic and benefit-seeking reasoning among thought-disordered subjects, emphasizing both the strengths and weaknesses of their thinking. Because of differences in severity of illness, cognition, and reasoning among those who decline research participation, greater attention to this population appears warranted.
Acknowledgments
This work is supported by a Mentored Scientist Development Award to Dr. Candilis (K01MH01851). The views expressed in this article do not necessarily reflect those of the National Institutes of Health.
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