Demographically adjusted CERAD wordlist test norms in a Norwegian sample from 40 to 80 years

Figures & data

Figure 1. Flowchart depicting an outline of the participant inclusion process from the Trønderbrain and DDI cohorts and workflow of the paper.

Table 1. Cumulative percentiles for the CERAD WLT recognition subtest.

	Non-geriatric (≤64 years)			Geriatric (≥65 years)
	Male n = 33	Female n = 52	Total n = 85	Male n = 26	Female n = 34	Total n = 60
Age range (mean)	45–64 (57.8)	40–64 (54.8)	40–64 (55.9)	65–80 (70.4)	65–78 (69.6)	65–80 (69.9)
Mean (SD)	19.2 (1.1)	19.8 (0.6)	19.6 (0.9)	19.0 (1.7)	19.2 (1.2)	19.1 (1.4)
Range	16.0–20.0	17.0–20.0	16.0–20.0	13.0–20.0	15.0–20.0	13.0–20.0
2%	16	17	17	13	15	13
5%	17	19	17	14	17	15
10%	17	19	19	16	18	17
25%	19	20	19	19	19	19
50%	20	20	20	20	20	20
75%	20	20	20	20	20	20
90%	20	20	20	20	20	20

Notes. n: Number of participants; SD: standard deviation.

Table 3. Normative regression models for CERAD WLT Learning and Recall subtests.

Variable	Predictor	B	Standard error B	T	SD residual
CERAD Word list Learning
	Constant	14.195	1.600	8.871	2.54678
	Age	−0.100	0.020	−5.024
	Gender	1.060	0.354	2.992
	Education	0.113	0.053	2.125
CERAD Word list Recall
	Constant	13.756	1.571	8.759	2.51947
	Age	−0.093	0.020	−4.752
	Gender	1.176	0.350	3.359
	Education	0.107	0.052	2.045

Notes. B: unstandardized regression coefficient; T: the t test statistic; SD: standard deviation.

Table 4. Demographics, raw scores and T scores of the healthy controls and MCI group.

	Healthy controls n = 227	MCI group n = 168
Variables	Test scores/demographics	Test scores/demographics	Sig.
Age	63.1 (8.6) [40–80]	64.4 (9.4) [40–80]	n.s*
Gender (% females)	62	54
Years of education	14.2 (3.2) [7–23]	13.6 (3.4) [7–22]	n.s*
CERAD WORD LIST (30) LEARNING
Raw score	21.5 (3.3)	16.9 (4.3)	p < .0001*
T score	50.0 (10.0)	38.7 (10.1)	p < .0001*
CERAD WORD LIST (10) RECALL
Raw score	7.2 (2.0)	4.3 (2.7)	p < .0001*
T score	50.0 (10.0)	37.4 (11.4)	p < .0001*

Notes. n: Number of participants; MCI: mild cognitive impairment; Sig.: significance tests; p: p value; T: T score; n.s.: non-significant result. Results are presented as mean (standard deviation) [range] except for gender which is characterized by female percentage. *Summary independent T tests. Significant p values are shown in bold.

Table 2. Raw score to scaled score conversions.

Scaled score	CERAD learning	CERAD recall
3		≤1
4	≤13	2
5	14–15	3–4
6	16–17
7	18	5
8	19	6
9	20
10	21–22	7
11	23	8
12	24
13	25	9
14	26	10
15	27
16	28
17	≥29

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, B-E.K. The data are not publicly available due to restrictions e.g. their containing information that could compromise the privacy of research participants.