An Online Decision Aid for Patients With Metastatic Melanoma

Results of the Randomized Controlled Trial “PEF-Immun”

Background: Treatment decisions in metastatic melanoma (MM) are highly dependent on patient preferences and require the patients’ involvement. The complexity of treatment options with their individual advantages and disadvantages is often overwhelming. We therefore developed an online patient decision aid (PtDA) to facilitate shared decision making (SDM).

Methods: To evaluate the PtDA we conducted a two-armed, two-center, prospective, open randomized controlled trial with MM patients who were facing a decision about first-line treatment. The patients were allotted randomly in a 1:1 ratio to an intervention group (IG) with access to the PtDA before discussion with a physician or to a control group (CG) without access to the PtDA. The primary endpoint was knowledge about the options for first-line treatment (multiple-choice test, 10 items, range 0–40 points). The secondary endpoints were the SDM (third-party ratings of audio recordings of the treatment discussions) and satisfaction with the decision at the follow-up visit.

Results: Of the 128 randomized patients, 120 completed the baseline questionnaire and were analyzed (59% male, median age 66 years). The primary endpoint, i.e., the mean difference in knowledge after discussion with a physician, differed significantly between the IG and the CG (−3.22, 95% CI [−6.32; −0.12], p = 0.042). No differences were found for the secondary endpoints, SDM and satisfaction with the decision. The patients in the IG rated the PtDA as very useful.

Conclusion: The PtDA improved the knowledge of patients with MM about the options for treatment. Both groups were highly satisfied with their treatment decisions. However, additional physician training seems necessary to promote SDM.

Metastatic melanoma (MM) is responsible for < 90% of deaths from skin cancer (1). The introduction of immune checkpoint inhibitors and targeted therapy with BRAF/MEK inhibitors has greatly improved survival rates. However, the different treatment options vary in efficacy and risks, so that shared decision-making (SDM) with patients is recommended for individual selection of the most suitable first-line treatment.

Compared with monoimmunotherapy, combined immunotherapy using the CTLA-4 inhibitor ipilimumab and the PD-1 inhibitor nivolumab in immune checkpoint therapy achieves higher response rates and improved progression-free survival, but does not lead to a significant improvement in overall survival (2, 3, 4, 5). Both forms of immunotherapy can bring about long-term control of the tumor disease. However, severe adverse events occur more frequently with combined immunotherapy than with monoimmunotherapy (5, 6); both can lead to long-term, potentially fatal adverse events (7).

For melanomas with the BRAFV600 gene mutation (about 50% [8]), targeted therapies (BRAF/MEK inhibitors) have initially high response rates. Resistance develops after a median of 11–15 months, however, meaning that the likelihood of long-term control of the tumor disease is lower than with immunotherapy (9, 10, 11, 12, 13). Severe adverse events often occur, but are reversible after drug discontinuation (14).

The German clinical practice guideline recommends SDM for melanoma treatment decisions, considering the patients’ individual preferences, the available options, and the associated risks (1). Research indicates that patients with melanoma want to be involved in treatment decisions (15), but often feel insufficiently informed to participate actively (16). Moreover, online information on melanoma is often difficult to understand and inaccurate (17). To facilitate SDM and improve patient knowledge, it is crucial to provide unbiased, readily understandable, evidence-based information about treatment options. Online patient decision aids (PtDAs) can serve to educate patients, enhance their autonomy, and improve the quality of medical consultations (18). Due to the complexity of MM treatments, physicians involved in consultations often lack sufficient time and specific SDM communication skills to document and discuss patient preferences. A PtDA could be a valuable resource in this context.

We therefore developed, in 2019, an interactive online PtDA for first-line treatment in MM and evaluated its benefits in a randomized controlled trial (“PEF-Immun”) with patients at the skin cancer centers of the National Centers for Tumor Diseases (NCT) in Heidelberg and Dresden.

We compared an intervention group (IG) that had additional access to the PtDA with a control group (CG) that received only the standard consultation to discuss treatment (treatment as usual, TAU). We hypothesized that immediately after the physician consultation the IG would have a higher level of knowledge than the CG about the treatment options for MM. Furthermore, we investigated whether the two groups differed in the objective scope of SDM during the consultation or in satisfaction with the decision at the time of follow-up.

Material and methods

Development and structure of the decision aid

The PtDA was developed in accordance with the International Patient Decision Aids Standards (IPDAS) (19) and meets high quality criteria (20) (eSupplement-Methods “International Patient Decision Aids Standards Checklist”). A prototype based on a literature review (6, 9, 10, 13, 14, 21, 22, 23, 24, 25, 26, 27) was improved through user participation (focus groups and surveys with patients, patient representatives, and experts). The final version of the online PtDA comprises nine webpages, including an interactive component. Programing was performed by TAKEPART Media + Science (28).

The PtDA contains information on the disease (including its natural course without treatment) and on the benefits and risks of the first-line treatment options (PD1-directed monotherapy, combination immunotherapy, targeted treatment with BRAF/MEK inhibitors, treatment as part of a clinical trial), all in plain, lay-friendly language. Complementary medicine and the no treatment option are discussed in brief. Animations, videos, and interviews are included to facilitate understanding. Response rates, survival rates, and adverse effects are illustrated with risk diagrams. Interactive elements help patients to clarify their attitudes, and an individual result report is generated from their answers. A summarizing flyer comes with the PtDA.

A PtDA session takes 20–30 minutes. The materials can be found under “Screenshots PtDA”, “Flyer,” and “Result Report PtDA” (eSupplement-Methods). The PtDA is updated regularly with the latest study results (most recently in January 2023) and is freely accessible (in German) at www.melanom-entscheidung.de under the aegis of the Dermatological Oncology Study Group (Arbeitsgemeinschaft Dermatologische Onkologie, ADO).

Assessment of the benefit of the PtDA: randomized controlled trial

Inclusion criteria: We included patients > 18 years, fluent in German, with inoperable stage III or IV melanoma scheduled for first-line treatment at the skin cancer center of NCT Heidelberg or Dresden (Germany). Patients with limited legal capacity or with cognitive, mental, or physical impairments affecting PtDA processing were excluded.

Study arms: Eligible patients were randomized to the IG or CG, using the online tool https://randomizer.at, in a 1:1 ratio, stratified by study center. We used block randomization with a block size of 8 (this was unknown to the study teams). The patients in the IG were provided with the PtDA (tablet) and the accompanying flyer before the medical consultation to discuss their treatment. Physicians were encouraged to review the results report in advance to prepare for the consultation. The CG patients underwent TAU and received information on treatment options solely during the medical consultation. Blinding of patients and physicians was not possible due to the nature of the intervention.

Data collection: The participating patients completed questionnaires at three time points: T0 (baseline, before the consultation), T1 (0–10 days after the consultation), and T2 (follow-up, 70–98 days after the consultation). The follow-up questionnaires were handed out personally or sent by mail prior to the pending staging visit. Audio recordings of the medical consultations were transcribed word for word and analyzed. Detailed descriptions of the study procedures can be found in the published study protocol (28).

Endpoints: The primary endpoint was the level of knowledge about treatment options for MM at T1. The knowledge test was a piloted multiple-choice test with 10 questions. A a weighted sum score was calculated (range 0–40 points; see eSupplement-Methods “Knowledge Test”). A pilot study (N = 24) assessed the comprehensibility and quality of the questions. The internal consistency of the knowledge test can be described as good (Cronbach’s α = 0.87) (28).

The secondary endpoints included decision satisfaction (German version of the Satisfaction with Decision Scale, SwD [29]) at T2 and SDM quality (third-party rating of SDM quality during the recorded medical consultation (OPTION-5 scale [30, 31]). SDM quality was rated independently by two trained members of staff. The raters were blinded to group allocation. In a few cases, however, blinding was undermined by mention of the PtDA in the audio recordings. For statistical analysis, the mean value of the two raters’ assessments for each item was used to calculate a rescaled sum score for all five items (range 0–100).

Additional information documented included sociodemographic data (MM patients and physicians), disease-related variables (e.g., treatment decision, adverse events), quality of life (global health status, questionnaire QLG-C30 of the European Organization for Research and Treatment of Cancer, EORTC [32]), control preferences in treatment decisions (Control Preferences Scale, CPS [33]), and subjective perception of knowledge level (visual analog scale, range 0–100). The IG patients rated the usefulness and acceptability of the PtDA (Likert scale, 1 [“strongly disagree“] to 7 [“strongly agree“]).

Reporting guidelines: The article was written in accordance with the CONSORT statement for randomized controlled trials (eSupplement-Methods “CONSORT Checklist” [34]) and the SUNDAE Checklist for evaluation studies of PtDAs (eSupplement-Methods “SUNDAE Checklist” [35]).

Artificial intelligence: ChatGPT was used for support in shortening the original manuscript.

Statistical analyses

Patient and physician characteristics are summarized by absolute and relative frequencies for categorical variables (n, %) and by means with standard deviations (SD) for metric variables. All analyses are based on the modified intention-to-treat (mITT) dataset, consisting of all randomized patients, except those for whom no data were documented. Missing data were imputed using multiple imputation. Twenty datasets were generated and the results were pooled using Rubin’s rule (36) (eSupplement-Methods “Imputation of missing Data”). The group difference for the primary endpoint knowledge (points scored in knowledge test at T1) was determined by linear regression (α = 5%). We report the adjusted mean scores, the two-sided 95% confidence interval (CI) and the p-value. The covariates were initial knowledge at T0, age, education level, and study center.

For the secondary endpoints, we also conducted linear regressions to explore group differences in the adjusted means (p-values were interpreted descriptively). In the regression model for SDM quality (OPTION score T1), the covariates were age, education level, and duration of consultation. In the regression model for satisfaction with decision (SwD score T2), the covariates were age, study center, and quality of life (EORTC Global Health Score at T0). For all endpoints sensitivity analyses were performed on the complete case dataset and the per-protocol dataset (for protocol violations, see eSupplement-Results “Sensitivity Analyses”). Descriptive statistics were compiled for evaluation of the usefulness and acceptability of the decision aid.

All analyses were performed using the software SAS (9.4) and IBM SPSS Statistics (28.0).

Ethics approval: The study was carried out in adherence to the Declaration of Helsinki. Approval was granted by the ethics committees of Heidelberg University Hospital (S-436/2019) and Technical University Dresden (EK 529122019). The participants provided written informed consent.

Results

The recruitment phase ran from February 2020 to August 2022. A total of 128 patients met the inclusion criteria, provided informed consent (response rate 64.5%) and were randomized. Two patients meeting exclusion criteria were mistakenly randomized and later withdrawn, leaving 126 valid randomizations. At T0 there were data for 120 patients, who thus formed the final sample (mITT dataset). Figure 1 provides a detailed overview of the patient flow and the composition of the dataset for analysis of the primary hypothesis. In 11 cases the intervention was not carried out correctly (mainly due to technical problems, e.g., WiFi breakdown, no sound).

Figure 1

Consort flow diagram, randomized controlled trial (RCT)

Table 1 shows the baseline patient characteristics and descriptive statistics for the endpoints.

Table 1

Baseline patient characteristics

Further disease-related variables (e.g., tumor status, treatment decision) and physicians’ characteristics as well as the survival curves can be found in eSupplement-Results: “Clinical Outcome”.

Primary and secondary endpoints

Confirmatory analysis of the primary endpoint knowledge at T1 showed that the IG patients, who had access to the PtDA, achieved higher scores than the CG patients (no PtDA access) (Table 2). The adjusted means of the two groups differ significantly : −3.22 [−6.23; −0.12], p = 0.042, Cohen’s d = −0.37.

Table 2

Analysis of the primary and secondary endpoints in the mITT set

No group differences were found for the secondary endpoints SDM quality (T1) and decision satisfaction (T2) (Table 2). The sensitivity analyses revealed no differences between the two groups (eSupplement-Results “Sensitivity Analyses”: eTables 3–6).

Descriptive analyses showed that at T1, the IG patients subjectively felt better informed (M = 81.7, SD = 14.7) than the CG patients (M = 75.9, SD = 14.6). The IG patients rated the PtDA as very useful (Table 3). In both groups, the OPTION scores were highest for item 3 and lowest for item 5 (Figure 2). Concordance between raters was high (rOPTION score = 0.89, p < 0.001).

Figure 2

Mean scores for individual OPTION 5 items

Table 3

Subjective acceptability and usefulness of the PtDA

Discussion

In this study we developed a PtDA for patients with MM to enhance their knowledge about the options for treatment and to facilitate SDM in medical consultations. The benefit of the PtDA was evaluated in a bicentric randomized controlled trial (RCT). The PtDA significantly increased patients’ knowledge on treatment options. Exploratory analyses found no clinically relevant effects on SDM quality or decision satisfaction.

Our findings are consistent with previous studies demonstrating that PtDAs effectively enhance patient knowledge (18). The effect size is small but stable, as evidenced by consistent mean differences between the groups in per-protocol and mITT analyses.

When comparing the effect size to those of RCTs on other PtDAs, it should be noted that our study featured a strict control group. The similar duration of the medical consultations in the two groups indicates that physicians explained the treatment options comprehensively regardless of study group, probably partly because they knew that the conversations were being recorded and they were “under observation”. This is supported by high ratings for OPTION item 3 (“The clinician gives information or checks understanding about the options that are considered reasonable”). Given the Hawthorne effect, the impact of the PtDA on patient knowledge may even be underestimated.

In contrast, we found no effect of the PtDA on SDM quality. The latter was rated low in both groups, comparable to other studies with physicians not trained in SDM (37). The physicians in our study performed very well in providing treatment information, but showed limited engagement with patient preferences and integration of these into the treatment deliberations. Previous research partially showed that PtDAs positively influence physician‒patient conversations (18). The low ratings for SDM quality and for several OPTION-5 items in both groups highlight the importance of SDM training for physicians to improve these skills.

Both groups of patients were highly satisfied with their treatment decision at 3-month follow-up. The well-known ceiling effect for satisfaction measures may have contributed to the fact that not even small effects could be detected in our study. Nevertheless, research has shown that PtDAs can increase confidence and decision satisfaction among oncology patients (18).

Our study has a number of strengths, including successful randomization, which minimized bias by distributing relevant variables equally between the groups. The sample was sufficiently diverse in terms of sociodemographic data. There was a higher proportion of male patients (59%), reflecting the somewhat higher incidence of MM in men (38). The study results show high ecological validity and can be applied for use of the PtDA in routine clinical practice because the study design largely aligned with usual care.

However, the study also features limitations. For example, the usefulness and acceptability of the PtDA were assessed only by patients; physicians’ views on this topic were not systematically sought. It cannot be excluded that the patients’ highly positive rating was influenced by selection bias. Additionally, the widely used OPTION-5 instrument (39) may not be ideal for measuring SDM quality in our study design, as it focuses primarily on the physicians’ behavior during assessment (40) and does not capture active patient participation, which was probably more likely to be influenced by the PtDA. At the time of development of the PtDA in 2019, no study results on overall survival or quality of life were available; however, these are important decision criteria for patients. Data on these factors are now available and will be included in the next update.

Conclusion

Previous research has emphasized the need for patient-friendly online resources on MM, particularly about complex immunotherapies (17). For the purposes of the study presented here we developed an effective online decision aid that improved patients’ knowledge compared with standard care. Patients found the PtDA acceptable and useful. However, we found no clinically relevant effect on the SDM quality of medical consultations. Although the physicians performed very well in providing information, engagement with patient preferences and integration of the latter into treatment deliberations leaves much to be desired.

Promotion of SDM evidently requires additional measures targeted specifically at physicians’ communication skills. Combination of the PtDA with SDM training for physicians is therefore urgently recommended.

Acknowledgments

First of all, we thank all of the patients and colleagues who contributed to the creation process of the PtDA and the study. We thank Stanley Krickmann, Martin Salzmann, and Timo Schank for their exceptional dedication to patient recruitment and TAKEPART Media + Science GmbH for excellent collaboration in the development phase of the PtDA.

Data availability

Data supporting the results reported in the article can be provided upon request.

Funding information

The study “PET-Immun” was funded by the Innovation Fund of the Federal Joint Committee (https://innovationsfonds.g-ba.de/innovationsausschuss), with financial support of € 575 000 over 4 years (January 2019–December 2022).

Conflict of interest statement

FM has received honoraria for talks from Novartis, Pierre Fabre, BMS, and MSD for participation in advisory boards and for talks at training courses/congresses. However, decision aids were never the topic of these events.

JCH has received research funds from BMS. The sums concerned went directly to the university hospital. She has also received honoraria for talks from BMS, MSD, Novartis, and Pierre Fabre as well as congress fees from BMS.

The other authors declare that no conflict of interest exists.

Manuscript received on 15 September 2023, revised version accepted on 11 March 2024.

Corresponding author
Prof. Dr. med. Christiane Bieber

Klinik für Allgemeine Innere Medizin und Psychosomatik

Zentrum für Psychosoziale Medizin
Universitätsklinikum Heidelberg

Thibautstr. 4
69115 Heidelberg, Germany

Cite this as:
Grabbe P, Borchers MS, Gschwendtner KM, Strobel S, Wild B, Kirchner M, Kälber K, Rendon A, Steininger J, Meier F, Hassel JC, Bieber C: An online decision aid for patients with metastatic melanoma—results of the randomized controlled trial „PEF-Immun“. Dtsch Arztebl Int 2024; 121: 385–92. DOI: 10.3238/arztebl.m2024.0053

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