Group or One-on-One? Systematic Review Finds No Clear Winner in Rehab Therapy Formats

When patients are prescribed physiotherapy, occupational therapy, or speech therapy, the format of delivery is often decided by logistics rather than evidence. Group sessions promise efficiency, shared motivation, and shorter waiting lists, while individual sessions offer undivided therapist attention. A new systematic review published in Frontiers in Rehabilitation Sciences has now tackled this question head-on, and its answer is strikingly inconclusive: for the vast majority of measured outcomes, neither format clearly outperforms the other.

The research team, led by Michael Minor of the Essener Forschungsinstitut für Medizinmanagement (EsFoMed) in Essen, Germany, searched Embase, PubMed, and Web of Science through May 2025. Following the Cochrane Handbook and reporting under the PRISMA 2020 checklist, they screened more than 7,000 records and ultimately included eleven randomized controlled trials: eight in physiotherapy, two in speech therapy, and one in occupational therapy. Crucially, the team only accepted studies in which the group and individual interventions followed identical therapy protocols, ensuring that any observed differences could be attributed to the delivery format rather than the treatment content itself.

The scope of the included trials was remarkably broad. In physiotherapy, studies examined constraint-induced movement therapy, task-oriented circuit training, and mirror therapy for stroke patients, exercise training for children with developmental coordination disorder, pelvic floor muscle training for women with stress urinary incontinence, multimodal programs for Parkinson’s disease and chronic knee pain, and strength training for resistance-trained men. The speech therapy trials covered voice therapy for children with vocal fold nodules and narrative-based language intervention for children with cochlear implants, while the single occupational therapy study applied a developmental floortime model to toddlers with autism.

Across these eleven trials, the researchers evaluated 76 distinct outcomes spanning motor function, voice-related measures, adaptive behavior, activities of daily living, pain, quality of life, and process indicators such as attendance and satisfaction. The headline finding is that 67 of those 76 outcomes showed no statistically significant difference between group and individual therapy after intervention. Group therapy produced better results in five outcomes, individual therapy in four. In other words, the delivery format appears to matter far less than the therapy itself.

Some nuances emerged within the noise. In stroke rehabilitation, group-based circuit training and constraint-induced movement therapy occasionally favored the group format, with one trial reporting significantly higher gait speed gains measured by the six-minute walk test, and another showing larger improvements on the Motor Activity Log and Action Research Arm Test in group participants. Conversely, a mirror therapy trial found that resistance to passive movement of the finger flexors improved more in individual sessions. In the voice therapy study, individual participants achieved a higher s/z ratio while group participants scored better on the noise harmonic ratio. Therapists in the pediatric voice study also noted that group sessions were more enjoyable, with patients appearing more competitive and motivated.

One trial stood apart for its focus on healthcare delivery rather than clinical endpoints. It found that group therapy participants waited fewer days before starting treatment, allowing earlier intervention, while staff burden did not increase and nonattendance rates remained similar to individual care. This process advantage is significant given the scale of demand: in Germany alone, roughly 334 million treatments were performed in 2025, with physiotherapy accounting for approximately 271 million of them. Yet less than 0.1 percent of physiotherapy treatments, 1.6 percent of occupational therapy treatments, and 0.5 percent of speech therapy treatments were delivered in group format, despite policy that nominally prioritizes group delivery for cost-effectiveness.

The methodological verdict, however, tempers any enthusiasm. Using the Cochrane RoB 2 tool, the reviewers judged eight of the eleven studies to carry a high overall risk of bias, with the remaining three raising some concerns; no study achieved low risk across all domains. High risks clustered around deviations from intended interventions and missing outcome data, often reflecting absent pre-registered protocols and unspecified analysis plans rather than clearly flawed conduct. Applying the GRADE framework, the certainty of evidence was rated low or very low for every outcome domain, driven primarily by the very serious risk of bias and, in most domains, cumulative sample sizes below 400 participants.

The heterogeneity problem proved equally formidable. Patient populations ranged from toddlers with autism to resistance-trained males, group sizes fluctuated between two and ten participants, interventions lasted from two to twelve weeks with sessions of 30 to 180 minutes, and outcome instruments varied from the Fugl-Meyer Test to the Adaptive Behavior Assessment System. Because effect estimates were not sufficiently comparable, the authors could not perform a meta-analysis and instead synthesized results narratively. Notably, every included trial was conducted in person; despite the search strategy permitting digital formats with synchronous video communication, no qualifying telemedicine studies were identified, leaving the effectiveness of digital group therapy entirely unexamined.

The authors are careful about what their null findings do and do not mean. Most trials were powered only to detect medium or large effects, so small but clinically meaningful differences may have gone undetected. Statistical non-significance, they emphasize, is not proof of equivalence; observing similar mean outcomes differs from demonstrating equal effectiveness. The findings align with prior reviews, including work on developmental coordination disorder, stroke and ischemic heart disease recovery, post-stroke upper limb interventions, and physical therapy for urinary incontinence and low back pain, all of which similarly failed to establish consistent differences between formats while acknowledging limited evidence quality.

The practical implications remain tantalizing but unproven. Group therapy could simultaneously treat more patients, shorten waiting times, and stretch limited rehabilitation resources, and the single trial measuring process indicators offered a glimpse of that promise. But with only eleven studies, pronounced imbalance across the three therapeutic disciplines, several small pilot trials, and no cost comparisons among the included studies, the review cannot yet declare which indications suit group delivery. The authors call for future research with strong methodological frameworks, adequately powered samples, and attention to both costs and treatment effects, particularly in speech therapy and occupational therapy where evidence remains scarcest. Until then, the choice between group and individual therapy rests on judgment, logistics, and hope rather than on solid evidence.

Subject of Research: Systematic review comparing group and individual therapy delivery formats across physiotherapy, occupational therapy, and speech therapy finds no clear evidence favoring either format.

Article Title: Comparison of group and individual therapy in physiotherapy, occupational therapy, and speech therapy: a systematic review

Article References: Minor, M., Plath, E., Volland, C., Neusser, S., & Bußmann, A. (2026). Comparison of group and individual therapy in physiotherapy, occupational therapy, and speech therapy: a systematic review. Frontiers in Rehabilitation Sciences, 7, Article 1904321. https://doi.org/10.3389/fresc.2026.1904321

Image Credits: AI Generated

DOI: 10.3389/fresc.2026.1904321

Keywords: group therapy, individual therapy, physiotherapy, occupational therapy, speech therapy, systematic review, rehabilitation, randomized controlled trials, risk of bias, GRADE, telemedicine, healthcare delivery