Table 3.

Multivariable logistic regression results for breed-related variables significantly associated with diagnosis of osteosarcoma amongst UK dogs

Variable	Variable P-value	Category	OR	95% CI	Category P-value
Purebred status	< 0.001	Crossbred	Base
		Purebred	1.35	1.18–1.54	< 0.001
		Unrecorded	0.52	0.33–0.79	0.003
KC Breed Group	< 0.001	Toy	Base
		Gundog	14.48	9.72–21.58	< 0.001
		Hound	21.54	14.14–32.81	< 0.001
		Not_KC_Recognised	7.10	4.75–10.59	< 0.001
		Pastoral	11.22	7.33–17.15	< 0.001
		Terrier	3.87	2.54–5.90	< 0.001
		Unrecorded	27.39	18.24–41.13	< 0.001
		Utility	2.42	1.49–3.94	< 0.001
Body mass (kg)	< 0.001	< 10	Base
		10–19.9	5.91	4.66–7.50	< 0.001
		20–29.9	7.31	5.75–9.30	< 0.001
		30–39.9	15.82	12.49–20.05	< 0.001
		> 40	18.07	13.87–23.53	< 0.001
		Unrecorded	0.15	0.10–0.22	< 0.001
Dachshund status	< 0.001	Non-Dachshund type	Base
		Dachshund type	0.15	0.05–0.46	0.001
		Unrecorded	0.70	0.61–0.79	< 0.001
Spaniel status	< 0.001	Non-Spaniel type	Base
		Spaniel type	0.37	0.29–0.47	< 0.001
		Unrecorded	0.65	0.57–0.74	< 0.001
Chondrodystrophy status	< 0.001	Non-chondrodystrophic	Base
		Chondrodystrophic	0.13	0.11–0.16	< 0.001
		Unrecorded	0.40	0.36–0.45	< 0.001
Skull shape	< 0.001	Mesocephalic	Base
		Brachycephalic	0.39	0.32–0.48	< 0.001
		Dolichocephalic	1.92	1.68–2.19	< 0.001

Legend: Full multivariable logistic regression results for variables significantly associated with diagnosis of osteosarcoma amongst UK dogs. The main model included breed-name as the breed variable (Table 2), and six breed-related variables (purebred-status, Kennel Club breed group, body mass, dachshund-status, spaniel-status, chondrodystrophy status) then replaced breed-name in the model (Table 3). Cases were dogs with osteosarcoma confirmed by analysis of biopsies submitted to VPG Histology between 2008 and 2020 and controls were dogs enrolled in the VetCompass™ database during 2016