Background
Musculoskeletal hand pain and hand problems are common in the general population1-4, with the hand being one of the most common sites of pain and osteoarthritis (OA) in older people5,6. Despite clinical history taking and physical examination being key to clinical decision-making7-10, few studies have considered the reliability of these methods of gathering information in those with undifferentiated hand pain presenting in primary care.
A Delphi study with 26 UK Health Care Practitioners11 identified a range of simple questions and physical examinations for use in primary care with older adults with self reported hand pain and problems. In this paper we describe the results of a reliability study in which we investigated the extent of inter-and intra-observer reliability for these, and some additional physical examination items, in a primary care population. Additionally, the reliability of applying the American College of Rheumatology (ACR) criteria for symptomatic hand OA12 is reported.
Methods
Ethical approval for the study was obtained from the North Staffordshire Local Research Ethics Committee (REC reference number: 02/54).
Observers
Observers were an Occupational Therapist and a Physiotherapist with 12 and 22 years post-qualification experience respectively. A manual of detailed protocols was developed and used to train and standardise the observers prior to the study, and for reference during the study. Briefly, these protocols outlined the objective, methods, recording instructions and special notes for each question and assessment. In addition, skip patterns for questions were described, and a detailed description was provided for each assessment, supplemented by photographs to aid standardisation. Prior to the study, both observers had undergone training in research interview procedures and physical examination techniques as part of another study13.
Participants
The sampling framework consisted of 201 people aged 50 years and over registered with one general practice who had previously completed a postal questionnaire as part of a study of hand pain and problems in the population14 and who fulfilled the following criteria: experienced hand pain or problems within the last 12 months (consultation was not required); completed questions on the presence of nodes and functional limitation; and consented to further contact. Exclusion criteria were accident, injury or surgery to the hands in the past month. A purposive sampling strategy based on presence of nodes and functional limitation was used to ensure that a spectrum of severity of hand problems and hand functional limitation would be represented in the study.
Procedure
Potential participants were sent a letter of invitation and an information sheet explaining the study and were asked to telephone the research centre if they were interested in participating. Those who did were screened for eligibility and were offered an appointment at a research clinic held at their general practice.
Consenting participants were asked to attend for two appointments, one month apart. At the first appointment, both observers independently assessed each participant. Allocation of participants to observers and the order of assessment were not randomised. However, by inviting participants to attend in pairs, so that each observer saw the same number of participants first and second, the potential for order effects was reduced. Observers were blind to the results of each other’s assessment and to existing data relating to participants’ hand problems. Participants were asked to complete a brief self-administered questionnaire.
At the second appointment, participants were assessed by one observer and repeated the brief self-administered questionnaire. To identify self-reported changes in overall hand problems between the first and second appointment, participants were asked to report whether their hand problem was “better,” “worse,” or “about the same.” To minimise missing data, a research nurse checked all assessment forms and questionnaires at both appointments.
Data collection
Clinical interview questions covered aspects of hand problems such as location (one or both hands, worst hand), handedness, history and duration, specific symptoms (pain, tenderness, aching or discomfort, stiffness, locking or triggering, altered sensation), functional limitation, impact of and adaptation to hand problems, self management, and causal and diagnostic attributions.
The physical examination included a screen of upper limb movement (adapted from15 to include radio-ulna supination and pronation, finger flexion and extension, wrist flexion and extension, and shoulder external rotation), observation of muscle wasting, observation and palpation of bony enlargement, deformity, swelling, and Dupuytren’s contracture, and palpation of joint pain and tenderness. Wrist and thumb range of movement and pain on resisted movement were also measured. Specific tests were carried out: Phalen’s16,17, Grind18,19, and Finklestein’s18,20. Sensation was evaluated using Semmes-weinstein™ monofilaments. Grip and pinch strength were measured using a Jamar dynamometer and a B&L pinch gauge respectively21, and hand function was assessed using the Grip Ability Test22.
In the self-administered questionnaire, participants completed the AUStralian CANadian Osteoarthritis Hand Index (AUSCAN)23 and answered questions about pain, stiffness and swelling in the hands and fingers, perceived hand strength, severity of hand pain (numerical rating scale), severity of hand problems and bothersome-ness of hand problems.
Statistical analysis
To detect a Kappa of ≥ 0.5 (two-tailed α = 0.05, power = 0.95) a minimum of 52 participants were required24. To allow for potential drop out we aimed to recruit 60 participants.
For categorical and numerical data, two analyses were carried out: inter-observer and intra-observer (test-retest) reliability. For categorical data, i