Efficacy of Pain Science Education Combined With Exercise in Older Adults With Chronic Pain

The Numeric Rating Scale (NRS) is a one-dimensional tool used to measure the intensity of pain perceived by an individual at a given time. It is based on self-assessment by the patient, who assigns a numerical value from 0 to 10 to their pain, where 0 indicates total absence of pain and 10 represents the worst pain imaginable. Pain between 1 and 3 is considered mild pain, between 4 and 7 moderate, and 8 to 10 severe. This variable is classified as a continuous quantitative variable. The NRS is administered in written form, is easy to understand, and does not require complex instruments, allowing its use in various clinical settings. It has been shown to be feasible and to show high correlations with other pain assessment tools. Furthermore, it is suitable for older adults with chronic pain participating in interdisciplinary pain rehabilitation.

The TSK-11 is a shortened self-report tool used to assess fear of movement. It consists of 11 items scored on a 4-point Likert scale (1 = strongly disagree to 4 = strongly agree), with a total score ranging from 11 to 44, where higher scores indicate greater levels of kinesiophobia. The TSK-11 was developed as a reduced version of the original 17-item scale after psychometric analysis identified six items with low statistical performance. Studies have shown that the TSK-11 has adequate internal consistency (Cronbach's alpha = 0.79), good test-retest reliability (ICC = 0.81; SEM = 2.54), as well as concurrent and predictive validity comparable to the original scale. It also demonstrated responsiveness to change (SRM = -1.11), making it suitable for evaluating therapeutic progress. This variable is considered continuous quantitative and is particularly relevant in research addressing psychosocial factors related to chronic pain and functional disability.

A 13-item self-report tool assessing negative thoughts about pain across rumination, magnification, and helplessness. Each item is scored 0-4 (total 0-52); higher scores indicate greater catastrophizing. It is reliable, valid, and important in chronic pain management.

An 8-item scale measuring pain intensity and disability (total 0-70). Quick to administer, reliable, valid, and useful for classifying pain severity and functional impact.

A 12-item questionnaire assessing physical and mental health-related quality of life. Produces standardized scores and is widely used in research and clinical practice.

For each patient, the following data were recorded: full name, ID number, phone number, sex, marital status, medical history, presence of chronic conditions (such as hypertension, diabetes, high cholesterol, hypothyroidism, among others), use of additional medications, number of tablets taken daily, number of analgesics taken daily, living situation, educational level, and general clinical condition. Blood pressure and heart rate were also measured to ensure that the patient was in optimal condition to undergo the evaluations.

A widely used tool in geriatric research to assess physical performance. It includes three tests measuring lower limb strength, gait speed, and balance. Total scores range from 0 to 12, with up to 4 points per component. Scores below 8 indicate low physical performance. The SPPB is quick, requires minimal equipment, and has high test-retest reliability, predictive validity, and clinical applicability.

Assesses mobility and balance by timing how long a person takes to stand from a chair, walk 3 meters, turn, return, and sit down. The test is performed twice, taking the best time. Times exceeding age-specific thresholds indicate below-average performance: >9.0s (60-69 years), >10.2s (70-79 years), >12.7s (80-99 years).

Measures grip strength quantitatively in kilograms. Performed seated with elbow at 90º and neutral hand position. Each hand is tested alternately, taking the average. The JAMAR dynamometer shows excellent reproducibility and interrater reliability and is considered the gold standard for handgrip assessment.

Evaluates the relationship between muscle force and contraction speed. Measured during five rapid sit-to-stand repetitions using a linear encoder attached at the waist, recording power, speed, and distance. Reliable in older adults and useful for performance optimization.

Weight (kg) divided by height (m²). Classifies individuals into ranges and serves as a screening tool for body composition and risk of chronic disease, though it does not directly measure fat percentage.

Indicates proportion of fat relative to total body weight. Normal ranges: men 12-20%, women 24-30%; obesity: men >25%, women >33%. Distribution (visceral vs. subcutaneous) is important for disease risk.

Fat surrounding internal organs, ~10% of total body fat, linked to higher risk of cardiovascular, metabolic, and other diseases.

Muscle mass in arms and legs. Measured via BIA, DXA, MRI, or anthropometry. BIA provides validated estimations of lean mass over time.

ASM adjusted for height (ASM/height²) to account for body size, as recommended by EWGSOP2.

Measured at the navel after full exhalation. Values >102 cm in men and >88 cm in women indicate increased health risk, providing information independent of BMI on central adiposity.

Quantitative Electroencephalography (qEEG) will be used to assess cortical activity. The signal will be decomposed using Fast Fourier Transform (FFT). The specific outcome is the mean absolute power in the Alpha frequency band (8-12 Hz) across the regions of interest (ROIs). Changes in alpha power are associated with pain modulation and central sensitization mechanisms. Unit of Measure:

Microvolts squared

Functional connectivity between brain regions will be assessed using spectral coherence indices derived from the qEEG. Coherence indicates the degree of synchronization between two brain regions at specific frequencies. Values range from 0 (no correlation) to 1 (perfect correlation). This metric evaluates the integration of neural networks involved in pain processing. Unit of Measure: Coherence coefficient (0-1)