Table 1.

Details of owners and cats involved in different stages of instrument development and validation including semi-structured interviews, field test 1 (item reduction and scoring algorithm generation) and field test 2 (validity and reliability testing)

Semi-structured interview	Field test 1 – online testing of prototype instrument	Field test 2 – testing for validity and reliability
• Cat owners (18: 5 males; 13 females) • Single and multi-cat households (2–4 cats) • Cat age range 1.75–21 years • 19 healthy and 10 sick (four OA and hyperthyroidism; two OA and CKD; four OA only)	• 71 single owner assessments (30 healthy cats; 41 sick cats) (43 males; 28 females) • Mean age of healthy cats 6.5 years (range 0.3–16.5 years) • Mean age of sick cats 11.5 years (range 1.2–19.5 years) • 66% DSH; 34% purebred (eg, Maine Coon, Persian, Siamese, etc) • 95% comorbidities (see Table 5 for conditions) • 29% of owners of unhealthy cats misclassified their cats as being healthy – in contrast to clinical assessment	• 94 single owner assessments (26 healthy cats; 58 sick cats) (48 male cats; 46 female cats) • 48 repeat assessments • Mean age of healthy cats 4.6 years (range 1–10 years) • Mean age of sick cats 11.7 years (range 1.1–19.9 years) • 86% DSH; 14% purebred • 72% comorbidities (see Table 5 for conditions) • 26% of owners of unhealthy cats misclassified their cats as being healthy – in contrast to clinical assessment

Demographics of cats include age, health status and presenting conditions, sex and breed. Misclassification between owner impression and clinician report of health status is reported for each study

OA = osteoarthritis; CKD = chronic kidney disease; DSH = domestic shorthair