Postoperative cognitive dysfunction: computerized and conventional tests showed only moderate inter-rater reliability.
OBJECTIVE
The incidence of postoperative cognitive dysfunction (POCD) depends on the test battery and calculation method used. The measurements may be performed with a paper and pencil test battery or with a computerized test battery. The objective of this study was to measure the incidence and congruence of POCD by comparing a computerized test battery with a paper and pencil test battery in the same patient population.


METHODS
In total, 67 patients were included: 30 consecutive in-patients undergoing surgery under general anesthesia and 37 non-surgical out-patients as control. Patients were tested with a paper and pencil test battery and a computerized test battery on inclusion in the study and 7 days later. Both test batteries covered the cognitive domains: visual attention, visual learning, memory, and speed of processing.


RESULTS
The computerized test battery classified 10.0% (95% CI 3.5-25.6%) of the patients as suffering from POCD whereas the paper and pencil test battery classified 30.0% (95% CI 16.7-47.9%) as suffering (95% CI for difference 3.9-36.5%, P = 0.03). The inter-rater reliability between both test batteries showed moderate agreement (Cohen's kappa of 0.41). All patients identified by use of the computerized test battery were also identified with the paper and pencil test battery. The paper and pencil test battery identified 6 additional cases.


CONCLUSIONS
In our study we demonstrated that the incidence of POCD measured with computerized test battery and paper and pencil test battery showed moderate inter-rater reliability. Use of neuropsychological test batteries theoretically covering the same cognitive domains does not automatically lead to the same classification of POCD.
Department of Anesthesiology and Surgical Critical Care Medicine, Campus Charité Mitte and Campus Virchow-Klinikum, Charité, Universitätsmedizin, Charitéplatz 1, 10117, Berlin, Germany.
Finn M
FM
Radtke
Martin
M
Franck
Norbert
N
Papkalla
Tim S
TS
Herbig
Edith
E
Weiss-Gerlach
Robin
R
Kleinwaechter
Klaus D
KD
Wernecke
Claudia D
CD
Spies
D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology*; D015331:Cohort Studies; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology*