Study of Effect of Age and Gender Related Differences on Common Paper and Pencil Neurocognitive Tests in Adolescents

Background: Neurocognitive tests are routinely used to assess cognitive domains in the adolescents for assessing cognitive deficits and for therapeutic interventions. Now they are being used to assess their mental abilities in athletics too. Aim: To study the effect of age and gender differences on routinely used common paper and pencil neuro-cognitive tests in adolescents and present the trends of normative data of Indian adolescent population. Settings and Design: Present study was conducted as a joint collaboration between Department of Physiology and Jawahar Navodaya school, Puducherry, India. Materials and Methods: Four hundred and thirty nine adolescents in the age group of 12 to 17 y (M = 250, F= 189) were selected in the present study after meeting the inclusion and exclusion criteria. Subjects were administered commonly used paper and pencil neuropsychological tests in the following order: Two Target Letter Cancellation test, Trail Making test A and B, Ruff Figural Fluency test (RFFT). Statistical Analysis: We divided the students based on their age into six groups - from age 12-17. Neurocognitive parameters were compared between these age groups using one-way-ANOVA with Bonferroni post-hoc test. Only the p-values for one, two and three year difference were considered. The same analysis was repeated for each gender separately. We compared males and females from the entire sample using unpaired t test. We then repeated the same test to compare males and females in each age group separately. Pearsons correlation was done to find correlation between the neurocognitive test parameters using the entire sample size. Then the correlation was done again after adjusting for age. All the statistical analysis was done using Statistical package for social sciences (SPSS) version 19. Results: Year wise normative data has been presented for all the age groups from 12 y onwards to 17 y. The results showed a consistent improvement in performance on the tested neuro-psychological tests with increasing age in adolescents. Overall gender comparison showed significantly better RFFT performance in males than females, with a non-significant difference in other tested parameters. However, no such difference was observed when the comparison was made within each age group. Conclusion: Improvement in the tests as a function of age may represent ongoing neuro-maturational process. Overall gender comparison from 12 to 17 y demonstrates that males performed better on nonverbal fluency task and strategic analysis suggesting difference in cognitive growth patterns but changes are so slow and gradual that no significant difference was observed at each intra-age group gender comparison. Baseline testing should be at least repeated once in two years.