The Effectiveness of a Physician-Led Web Portal on Back Pain

A Cluster Randomized Controlled Trial

Background: It is important for patients with back pain to be well-informed. The well-informed patient is better prepared for self-management and for joint decision-making with the physician. This is why we developed tala-med, a web portal providing up-to-date, evidence-based, independent information on back pain. Primary care physicians can use it in their practices and make it accessible to their patients.

Methods: A cluster randomized controlled trial (registration number DRKS00014279) was carried out in which the primary care physicians (PCPs) in the intervention group (IG: 33 physicians) were directed to use the tala-med web portal in their consultations with patients who had back pain (180 patients). The PCPs in the control group (CG: 12 physicians) were not given access to tala-med and treated their patients with back pain (136 patients) as they had done before. The patients’ informedness about back pain was the primary endpoint: it was assessed by the patients themselves in terms of their subjective degree of knowledge and subjective state of informedness about back pain. Pain intensity, the second endpoint, was assessed with a visual analog scale.

Results: Intention-to-treat analyses revealed that the patients’ subjective degree of knowledge about back pain increased to a greater extent in the intervention group than in the control group (B = 0.25, 95% confidence interval [0.07; 0.43]), as did their subjective state of informedness about back pain (B = 0.51 [0.13; 0.89]). Patients in the intervention group also reported a larger reduction of pain intensity compared to patients in the control group (B = −10.46 [−18.52; −2.38]).

Conclusion: Use of the tala-med web portal by primary care physicians and their patients made patients better informed about back pain and lessened the intensity of their pain. These improvements, although statistically significant, were not large enough to be clinically important.

Cite this as: Schlett C, van der Keylen P, Schöpf-Lazzarino AC, Röttele N, Körner M, Maun A, Meerpohl JJ, Horstmeier LM, Kaier K, Farin-Glattacker E, Voigt-Radloff S: The effectiveness of a physician-led web portal on back pain: A cluster randomized controlled trial. Dtsch Arztebl Int 2025; 122: 203–9. DOI: 10.3238/arztebl.m2025.0015

Lower back pain is one of the most common reasons for patients to visit their primary care physician (1); it is a major burden on both the healthcare system and patients’ quality of life (2, 3). In Germany, over 70% of adults experience at least one episode of back pain per year (4). Accordingly, back pain is one of the top three pain-related search questions on the internet (5). Especially since the COVID-19 pandemic, both patients and primary care physicians are increasingly turning towards the internet: While patients seek further information about their conditions (6), primary care physicians strive to incorporate online solutions into the care they provide (7, 8).

However, it is difficult to find good and reliable health information online (9) that is both trustworthy and easy to understand for the persons affected, as well as helpful and supportive for those providing treatment. This is particularly true for information about back pain, because of the many different treatment approaches that are used despite the existence of national and international treatment guidelines (10). As a result, patients searching the internet for health information about back pain can easily become frustrated and confused by the divergent and contradictory information (11). It is also not easy for primary care physicians to incorporate up-to-date, evidence-based, and independent information about back pain into their healthcare. Most academic journals provide this information only in English (at worst behind a paywall), and primary care physicians often lack the time to look up this information or present it to patients at the point of care (12).

Recent research has revealed that patients with back pain can benefit from digital health interventions if appropriate information is available and used (13, 14, 15). The findings show that such interventions have a small but clinically relevant effect on alleviating patients’ discomfort and disability (13). With regard to patients’ knowledge about back pain, however, a recent systematic review was unable to meta-analytically synthesize the current evidence and concluded that this topic remains inadequately explored (16).

Within the GAP project (the German acronym GAP stands for Gut informierte Kommunikation zwischen Arzt und Patient (well-informed communication between physician and patient), we developed the web portal tala-med for patients and primary care physicians (17). Tala-med provides up-to-date, evidence-based, and independent information on back pain in easy to understand language. Its content covers the epidemiology, etiology, symptoms, and the benefits and harms of treatment options for acute, subacute, and chronic back pain (17). With regard to patients, tala-med aims to enhance their state of informedness about back pain. A higher level of informedness should improve the self-management of back pain, and thus help patients to relieve their back pain. Being well informed should also facilitate patient participation and shared decision-making.

The aim of this study was to evaluate the effectiveness of tala-med with regard to the following patient-related endpoints:

• Primary endpoint
• Informedness about back pain
• Secondary endpoints
• Pain severity
• Quality of patient–physician communication
• Perceived efficacy in relation to patient–physician interactions
• Health literacy

Methods

Study design

We examined the effect of the use of tala-med compared to routine care (no use of tala-med) with a multicenter, cluster-randomized parallel group design. Each cluster comprised patients with back pain treated by the same primary care physician. Randomization took place at the level of primary care office in the ratio 2:1 (intervention group [IG] to control group [CG], stratified by the number of participating primary care physicians per office (1 versus 2–4 versus > 4; [17]). The results were reported in accordance with the CONSORT 2010 guidelines (eConsort-Checklist).

Data collection

Data were collected before (t0) and directly after the primary care physician consultation (t1) with (IG) or without (CG) access to tala-med. Follow-up (t2) took place after 3 weeks. IG patients had the opportunity to use tala-med on their own between t1 and t2.

Recruitment

The University Hospital Erlangen recruited primary care physicians working in Bavaria with support from the Bavarian Association of Family Physicians and General Practitioners (Bayerischer Hausärzteverband, BHÄV). Participating primary care physicians then recruited back pain patients among their clientele. Eligible for participation were patients aged 18 years or older who:

• Presented back pain symptoms
• Were insured by a company health insurance fund
• Provided written informed consent for study participation
• Had sufficient German language skills to complete the questionnaires

Sample size calculation

The estimated required sample size for the primary endpoint was N = 666 (IG: n = 444; CG: n = 222). This sample size was based on an expected effect size of d = 0.30, an intraclass correlation of 0.01 (18), a cluster size of 10, a dropout rate of 35%, an α of 5%, and a power of 0.80.

Intervention

Tala-med is a German-language web portal on back pain that aims to improve patients’ informedness by providing evidence-based, comprehensive, and reliable information. The content of tala-med is based on the German National Disease Management Guideline for non-specific lower back pain (19), and has been aligned with three international guidelines on lower back pain (20, 21, 22). To meet the demands and linguistic level of primary care physicians and patients, tala-med offers a distinct, tailored version for each group (23). The primary care physicians were instructed to use their version of tala-med during their consultations and encourage their patients to use the patient version of tala-med at home. They were also asked to show and recommend to their patients any features of the portal they considered especially helpful.

The intervention included one primary care physician consultation with tala-med and 3 weeks’ use of the web portal by the patient. During the randomized controlled trial, the primary care physicians and patients had individual log-ins to access their respective version of tala-med. Tala-med was made publicly accessible (https://ruecken.tala-med.info/) after the trial concluded and has remained freely available since then.

Recording of endpoints

The primary endpoint, patient informedness, was assessed using two co-primary (24) indicators:

• Self-rated knowledge about back pain, measured before (t0) and after the intervention (t2)
• Perceived informedness about back pain, as conveyed by the primary care physician and the intervention, measured after the intervention (t2)

As no suitable, valid, and reliable measures existed (16), we developed new scales for both indicators. To this end, we searched the literature to guide the formulation of the items and then conducted cognitive pretests with N = 8 patients with back pain (17) to ensure the items’ comprehensibility and acceptability (eSupplement-Table 1). The final scales comprised seven and 11 items (eSupplement-Scales) and showed good internal consistency (Cronbach’s alpha ≥ 0.86). Exploratory factor analyses confirmed that the two scales are unidimensional and empirically distinct, although related (eSupplement-Methods). The secondary endpoint back pain severity referred to the last 7 days and was assessed with a visual analog scale ranging from 0 to 100 (25) before (t0) and after the intervention (t2). In addition to these back pain-specific endpoints, we used validated scales to assess patients’ perception of the quality of the patient–physician communication (26, 27, 28, 29, 30) after the primary care physician consultation (t1) as well as their perceived efficacy in patient–physician interactions (31) and health literacy (32, 33) before (t0) and after the intervention (t2).

Analyses

The main analyses were intention-to-treat analyses with multiple imputation of missing values and propensity score adjustment (34). Hypotheses on the two co-primary indicators were examined with linear mixed models with the variables group (IG versus CG) and propensity score as fixed effects and patients’ affiliation to a primary care physician as a random intercept. Specifically, the linear mixed model for self-rated knowledge about back pain examined whether the change from t0 to t2 differed between the IG and the CG, whereas the model for perceived informedness about back pain examined whether the scores at t2 differed between IG and CG (eSupplement-Methods). The significance level was set at 5% for all analyses. As effect size measures, we report the standardized effect size d and the number needed to treat (NNT; eSupplement-Methods).

Results

The recruitment of patients started in September 2018 and ended in September 2020 before the planned sample size was reached, because the spread of the COVID-19 virus led to overburdening of primary care physicians and precluded further enrollment. Of the 83 primary care physicians randomized in the study, 45 (54%) recruited 316 patients (Figure). Characteristics of the patients, the primary care physicians and their offices are shown in eTables 1–3. All characteristics shown were included in the propensity score.

Figure

Flow chart of participating primary care physicians, offices, and patients

eTable 1

Sample of patients

eTable 2

Sample of primary care physicians

eTable 3

Sample of physicians’ offices

Missing data and imputation

The dropout rate from t0 to t2 was 28% (eSupplement-Table 2). After dropout analysis, we replaced missing values by multiple imputation to ensure valid hypothesis testing (35) (eSupplement-Methods).

Primary and secondary endpoints specific to back pain

Intention-to-treat analyses showed that patients in the IG gained significantly more knowledge about back pain from t0 to t2 than patients in the CG (B = 0.25 [0.07; 0.43]; Table 1). With an effect of d = 0.39, NNT = 5, the intervention had a small to medium effect size (36, 37). Intention-to-treat analyses also showed that patients in the IG showed significantly higher levels of perceived informedness about back pain than patients in the CG (B = 0.51 [0.13; 0.89]; Table 1). This effect was medium to large (d = 0.61, NNT = 3). Sensitivity analyses without propensity score adjustment and without imputation of missing values support these results by also showing significant small to medium effects (d = 0.28 to 0.43; NNT = 6 to 4; eSupplement-Table 3). Patients in the IG also showed a greater reduction in pain severity (secondary endpoint) than patients in the CG (B = –10.46 [−18.52; −2.38], d = −0.47, NNT = 4; Table 1). Portal usage statistics revealed that tala-med was used by patients for an average of 16 minutes (SD = 24 min; eSupplement-Table 4).

Table 1

Results of the intention-to-treat analyses on the primary and secondary endpoints (back pain-specific)

Secondary endpoints not specific to back pain

Patients in the IG rated the primary care physician’s communication behavior worse than those in the CG (B = –11.88 [−20.68; –3.08], d = –0.57, NNT = 3) and were less satisfied with it (B = –0.28 [−0.55; –0.02], d = –0.49, NNT = 4; Table 2). Post-hoc analyses revealed that patients in the IG only rated their primary care physicians’ communication worse when the latter did not use the web portal during the consultation (eSupplement-Table 5). When primary care physicians did use the portal during the consultation, patients rated their communication as more participatory and patient-oriented and reported a higher level of shared decision-making (eSupplement-Table 6). Compared with the CG, the IG also showed slightly higher increases from t0 to t2 in their perceived efficacy in patient–physician interactions and in aspects of health literacy related to having sufficient health information and feeling understood and supported by healthcare providers (d ≥ 0.29, NNT ≤ 6; p ≤ 0.033; Table 3).

Table 2

Results on the secondary endpoints, measured after the consultation with the primary care physician (not back pain-specific)

Table 3

Results on secondary endpoints measured before and after the intervention (not back pain-specific)

Discussion

Our study results provide evidence that the use of tala-med in primary care physician consultations and patient self-management led to statistically significant small to moderate improvements in the primary endpoint patient informedness about back pain. The improvements of 0.25 (self-rated knowledge) and 0.51 points (perceived informedness) on 5-point scales were below the minimally important difference of 15% of the scale range (38) and should therefore be considered as not clinically important. Use of tala-med also helped patients to reduce their pain severity. However, the reduction in pain severity of 10 points on a visual analog scale from 0–100 was also not clinically important. These positive effects on patient informedness and back pain correspond with the findings of the qualitative interview study with 32 patients from the IG (23). They are also consistent with the effects of digital self-management programs that aim at improvement of the understanding of back pain (39) and reduction of pain severity, for which a current meta-analysis reports small improvements immediately and shortly after the intervention (13).

The findings on secondary endpoints point to potential harm: Merely providing patients with tala-med, without a thorough introduction during the consultation, was detrimental to patient satisfaction with the patient–physician communication. This finding also matches with the qualitative study, in which patients expressed their disapproval of primary care physicians who used the portal inappropriately or not at all during the consultation (23). However, when primary care physicians introduced tala-med properly during the consultation, patients perceived its use as beneficial for their participation, shared decision-making, and patient–physician communication. Tala-med also seems to slightly improve patients’ perceived efficacy in patient–physician interactions, as well as their perceptions of being understood and supported by their healthcare providers and having sufficient health information.

Limitations

Although we assessed the primary endpoint with scales that showed good psychometric properties, these scales were newly developed. They assess patients’ self-rated informedness, which is prone to bias (40). However, the reduction in pain severity and the results of the process evaluation (23), suggest that patients’ gain in informedness was not only subjective, but also led to behaviors that helped them reduce their back pain. Another limitation is that the results of our study only permit conclusions about the short-term effects of tala-med, as the before and after measurements were only 3 weeks apart.

While the generalizability of the results is supported by the fact that the conduct of the study was supported in 34 offices with 45 primary care physicians, it is limited by the fact that our study included only patients insured by company health insurance funds. Future studies could investigate whether patients also benefit from tala-med if they use it before visiting their primary care physician (i.e., without guidance) and whether tala-med can also be used to enhance the informedness of people who are not directly affected by back pain, such as relatives or medical students.

Conclusion

The use of tala-med by primary care physicians and patients enhanced the patients’ informedness about back pain. Primary care physicians can thus use tala-med to help their patients to improve their informedness, alleviate their back pain, and facilitate their participation. However, primary care physicians should introduce the portal to their patients and integrate it into the care they provide. By doing so, they not only encourage their patients to use the portal (23) and increase its usefulness for them, but also avoid compromising patient–physician communication through superficial use of the portal. Our study suggests that primary care physicians could use web portals that provide up-to-date evidence-based health information about back pain to supplement their consultations. In this way, they will help patients find quality-assured health information which they can readily understand and use.

Acknowledgments
The authors thank Raphael Scheible and Martin Boeker for hosting and maintaining the tala-med user statistics with Matomo.

Ethics committee approval and consent to participation
The study plan was approved by the ethics committee of the University of Freiburg (No. 559–17). The ethics committee of the University of Erlangen concurred with the approval by the Freiburg ethics committee. The approval of the Ethics Committee of the University of Erlangen also covers all primary care physicians’ offices included in this study. All primary care physicians and patients provided written informed consent prior to their inclusion in the study.

Study registration
The study has been registered at the German Clinical Trials Register (DRKS00014279).

Funding
The trial was funded by the Innovation Committee of the Federal Joint Committee, grant number: 01NVF17010.

Data sharing statement
Data from this study are available to researchers who present a reasonable request to the corresponding author. The data will be provided in anonymized and aggregated form so that individual patients and primary care physicians cannot be identified.

Conflict of interest statement
The authors declare that no conflict of interest exists.

Received on 6 September 2024, revised version accepted on 23 January 2025

Corresponding author
Dr. rer. nat. Christian Schlett

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