. 2021 Apr 12;11:8000. doi: 10.1038/s41598-021-87287-8

Table 7.

Convergent and divergent correlational analysis (with coefficients correct for internal consistency) of the OCS-Plus sub-tasks.

OCS-Plus subtask	a	Task	Convergent validity				Task	Divergent validity
OCS-Plus subtask	a	Task	a	N	r	p	Task	a	N	r	p
Picture naming	0.23	ACE Naming	0.80	159	0.30	0.10	BDI	0.86	86	0.12	0.576
Picture naming	0.23	CERAD Boston Naming Task	0.56	86	0.29	0.32	ACE Visuospatial	0.80	159	0.29	0.103
Orientation	0.04	ACE orientation	.80	159	1^a	.009*	BDI	.86	86	.04	.942
Orientation							ACE visuospatial	0.80	159	− 0.01	0.979
Semantics	0.17	ACE language	0.80	159	0.71	< 0.001**	BDI	0.86	86	0.01	0.956
Semantics							ACE visuospatial	0.80	159	0.35	0.091
Encoding 1	.41	CERAD 1st Immediate Recall	0.62	86	0.32	0.08	BDI	0.86	86	0.01	0.931
Encoding 1							ACE visuospatial	0.80	159	0.35	0.005
Encoding 2	0.67	CERAD 2nd Immediate Recall	0.62	86	0.38	0.01*	BDI	0.86	86	− 0.1	0.414
Encoding 2							ACE visuospatial	0.80	159	0.24	0.022
Delayed recall	0.10	CERAD Delayed Recall	0.62	86	1^a	< 0.001**	BDI	0.86	86	− 0.08	0.788
Delayed recall							ACE visuospatial	0.80	159	0.12	0.145
Episodic recognition	0.06	ACE Memory	0.80	159	0.07	0.37	BDI	0.86	86	− 0.63	0.037*
Episodic recognition							ACE visuospatial	0.80	159	0.08	0.328
Rule finding	1						BDI	0.86	86	− 0.5	0.135
Rule finding							ACE language	0.80	159	0.06	0.834
Processing speed	1⁺	CERAD Trail Making Test A	1⁺	86	0.86	0.004*	BDI	0.86	86	0.12	0.136
Processing speed							ACE memory	0.80	159	− 0.05	0.416
Executive score	1⁺	CERAD Trail Making Test Time Ratio	1⁺	86	0	0.98	BDI	0.86	86	0.05	0.574
Executive score							ACE language	0.80	159	− 0.01	0.843
Cancellation	.96	Star Cancellation Missing	.89	85	− 0.24	0.03*	BDI	0.86	85	0.06	0.536
Cancellation							ACE language	0.80	159	− 0.04	0.63
Invisible cancellation	0.96						BDI	0.86	86	0.05	0.581
Invisible cancellation							ACE language	0.80	159	− 0.07	0.332
Figure copy accuracy	.94	ROCF Copy	0.60	86	0.32	0.005*	BDI	0.86	86	− 0.02	0.847
Figure copy accuracy							ACE language	0.80	157	0.05	0.510
Figure copy recall	0.93	ROCF 1st Recall	0.80	85	0.20	0.02*	BDI	0.86	86	− 0.15	0.077
Figure copy recall							ACE language	0.80	159	− 0.02	0.824

OCS-Plus Oxford Cognitive Screen-Plus, r Kendall correlation, BDI Becks Depression Index, ACE Addenbrookes Cognitive Evaluation, CERAD Consortium to Establish a Registry for Alzheimer's Disease, ROCF Rey–Osterrieth Complex Figure Test. Processing speed is correlated with ACE-Memory as arguably ACE-Visuospatial and -Language are related given anecdotal reports of patients talking themselves through the rule to follow which may add time and visuospatial skills. To check our assumption, we ran correlations between processing speed and both ACE-Visuospatial and -Language and both were small but significant. **Represent alpha corrected significance (convergent = 0.05/13 comparisons, divergent = 0.05/26), *Represents uncorrected alpha level at 0.05. ⁺Refers to assumed internal consistency measure due to measure being unable to generate internal consistency metric, e.g., in the case of time. Correlation coefficients were corrected for internal consistency such that the coefficient = coefficient/square root (internal consistency_x× internal consistency_y), where x and y are the OCS-Plus or validation measures. ^aRefers to corrected correlations that are greater than 1 which suggests the measurement error is not randomly distributed.