Participants will watch a brief video on pain neuroscience in which physiotherapist will not show evidence-based communication skills to effectively convey information to patients.

The Central Sensitisation Inventory (CSI) serves as a self-report tool aimed at identifying individuals with symptoms potentially linked to Central Sensitisation. The inventory consists of two parts. Part A involves 25 questions related to common Central Sensitisation Syndrome (CSS) symptoms. Patients rate each question on a scale from 0 (never) to 4 (always). A total score exceeding 40 suggests the presence of central sensitisation. In Part B, patients indicate if they have received a diagnosis for specific CSS disorders or related conditions, such as anxiety and depression. Notably, only the scores from Part A are considered in the assessment.

The Brief Illness Perception Questionnaire (B-IPQ) functions as an assessment tool for examining cognitive and emotional perceptions of illness. Comprising eight items, this questionnaire evaluates cognitive illness representation, emotional illness representation, and illness comprehensibility representation. Scoring involves rating each item on a scale from 0 to 10, where higher scores signify a more threatening perception of the illness. The total B-IPQ score is obtained by summing the scores of all eight items, resulting in a potential range of 0 to 80. Elevated scores on this scale indicate a more negative or distressing perception of the illness.

The 13-item scale is structured around three dimensions: rumination over pain, magnification of pain, and helplessness in the face of pain symptoms. Both the total score and subscale scores for the Pain Catastrophizing Scale (PCS) are calculated by adding up the ratings for each item. In this study, the focus is on the total score, which ranges from 0 to 52, with higher scores indicating a higher level of pain catastrophizing.

The State-Trait Anxiety Inventory (STAI) is a psychological assessment tool comprising 40 self-report items, rated on a 4-point Likert scale. This inventory is designed to gauge two distinct forms of anxiety: state anxiety and trait anxiety. Elevated scores on the STAI are positively associated with increased levels of anxiety.

This questionnaire serves as a tool for assessing the fear of movement or the fear of (re)injury in individuals experiencing pain. The resulting score can range from a minimum of 11 to a maximum of 44 points, with a higher score indicating a greater degree of kinesiophobia. A score of ≥18 is considered indicative of a fear of movement, and the severity of this fear escalates with higher scores.

Video Engagement was evaluated using the Video Engagement Scale (VES-sf). This questionnaire, designed to measure participants' engagement while watching a video, consists of eight items rated on a scale from 0 ('totally disagree') to 7 ('totally agree'). Scores on the VES-sf range from 0 to 56, with higher scores indicating greater engagement during video viewing. To determine participant inclusion or exclusion, the specific item 'I was fully concentrated on the video while watching' was utilized. Participants with a score lower than 3 on this item were excluded from the study.

The measurement of bonding in the context of patient-physiotherapist interactions is conducted using the Bonding scale of the Working Alliance Inventory - Short Revised (WAI-SR). Bonding, a crucial component of the working alliance, is defined as the collaborative, warm, and supportive connection between a patient and a therapist. The WAI-SR bond scale assesses the quality of this bond and comprises four items, each rated on a scale from 1 ('never') to 5 ('always'). Scores on the bond scale range from 4 to 20, with higher scores indicative of a higher perceived quality in the bond between the patient and the therapist.

The Global Rating of Change (GRoC) is a scale designed to evaluate the extent to which a patient's condition has improved, worsened, or remained stable, usually after receiving treatment. The GRoC typically involves a single question that prompts the patient to rate the change in their specific condition over a defined time frame. The GRoC is an 11-point scale, ranging from -5 (indicating a significant deterioration or being "very much worse") to 0 (representing no change or "unchanged") and up to +5 (indicating complete recovery or being "completely recovered").