Table 2.

Participants Classified as Impaired on NP Clinical Tests and CANTAB Tests by Study Group and Visit

NP Test, Impairment Criteria, and Time of Visit	Localized CRC							Metastatic CRC		Healthy Controls		P†	P‡
	CTh+		CTh–		P*	Total
	No.	%	No.	%		No.	%	No.	%	No.	%
Clinical NP tests
Overall cognitive impairment (GDS criteria)§
Baseline	77	44	48	41	.637	125	43	35	46	11	15	.671	< .001
6 months	53	41	33	37	.614	86	39	19	39	4	6	.967	< .001
12 months	55	49	35	40	.234	90	46	17	46	9	13	.915	< .001
24 months	36	38	23	32	.397	59	36	—	—	—	—	—	—
Overall cognitive impairment (ICCTF criteria)‖
Baseline	88	51	61	53	.774	149	52	32	46	12	17	.655	< .001
6 months	68	52	47	53	.850	115	51	28	57	9	13	.517	< .001
12 months	60	54	43	49	.606	103	52	20	54	13	19	.775	< .001
24 months	47	50	33	46	.594	80	48	—	—	—	—	—	—
CANTAB tests
Overall cognitive impairment (GDS criteria)§
Baseline	47	37	34	33	.49	81	35	19	33	8	11	.76	< .001
6 months	42	35	31	35	1.00	73	35	8	19	8	11	.048	< .001
12 months	34	32	20	24	.26	54	29	10	28	9	13	1.00	.009
24 months	20	22	12	17	.55	32	20	—	—	—	—	—	—
Overall cognitive impairment (ICCTF criteria)‖
Baseline	67	53	60	58	.51	127	55	38	66	13	18	.18	< .001
6 months	60	50	51	57	.33	111	53	15	36	20	29	.062	< .001
12 months	60	57	33	40	.027	93	50	20	56	18	26	.59	< .001
24 months	31	34	27	39	.51	58	36	—	—	—	—	—	—

Abbreviations: CANTAB, Cambridge Neuropsychological Test Automated Battery; CRC, colorectal cancer; CTh+, received adjuvant chemotherapy, CTh–, did not receive adjuvant chemotherapy; GDS, Global Deficit Score; ICCTF, International Cognition and Cancer Task Force; NP, neuropsychological.

^*Localized CRC: adjuvant chemotherapy v no adjuvant chemotherapy.

^†Localized CRC v metastatic CRC.

^‡Localized CRC v healthy controls.

^§Impairment defined as GDS > 0.5.

^‖Impairment defined as T score < 35 on two tests or T score < 30 on one test.