Academic Scientific JournalsRethinking cognitive assessment in mild intellectual disability: evidence-based recommendations for a person-centered diagnostic framework
Keywords:
disorders of intellectual development, cognitive assessment, CHC theory, adaptive behaviors, cognitive profilesAbstract
This article proposes a multidimensional, person-centered framework for diagnosing mild intellectual disability (MID), chal-lenging the traditional reliance on fixed IQ thresholds as the primary diagnostic criterion. Anchored in the Cattell-Horn-Carroll (CHC) theory of intelligence, the framework advocates for an integrative assessment approach that combines broad (Stratum II) and narrow (Stratum I) cognitive abilities with evaluations of adaptive behavior, clinical observation, and in-formant reports. This comprehensive model reflects the complexity and heterogeneity of MID, emphasizing that intellectual functioning cannot be accurately captured by a single numerical score. The framework underscores the importance of using ecologically valid and culturally sensitive tools, particularly for assessing functionally relevant domains such as memory, language, and literacy. It highlights the need for clinical judgment to be informed by structured tools that map individual cognitive profiles and guide intervention planning in alignment with real-world demands. Central to this approach is the recognition of intra-group variability and the presence of distinct cognitive subprofiles, which call for tailored interventions based on individual strengths and needs rather than rigid diagnostic categories. Drawing on recent empirical studies, the article provides evidence supporting the existence of these cognitive subtypes within MID populations and advocates for individualized, strength-based assessment and support strategies. It calls for a longitudinal, multi-method, and context-sensitive diagnostic process grounded in both theoretical models and clinical expertise. Ultimately, the proposed paradigm promotes diagnostic accuracy, ethical integrity, and equity by shifting from reductionist classification toward a nuanced understanding of cognitive functioning and human potential.
Downloads
References
Allison, L., & Strydom, A. (2009). Intellectual disability across cultures. Psychiatry, 8, 355–357. https://doi.org/10.1016/j.mppsy.2009.06.008
American Psychological Association (2022). Diagnostic and statistical manual of mental disorders (5th ed.). APA Publishing.
Bergeron, R., & Floyd, R. G. (2013). Individual part score profiles of children with intellectual disability: a descriptive analysis across three intelligence tests. School Psychology Review, 42, 22–38. https://doi.org/10.1080/02796015.2013.12087489
Blacher, J., Neece, C. L., & Paczkowski, E. (2005). Families and intellectual disability. Current Opinion in Psychiatry, 18, 507–513. https://doi.org/10.1097/01.yco.0000179488.92885.e8
Burchinal, M. R., Roberts, J. E., Hooper, S., & Zeisel, S. A. (2000). Cumulative risk and early cognitive development: a comparison of statistical risk models. Developmental Psychology, 36, 793–807. https://doi.org/10.1037//0012-1649.36.6.793
Burd, L., Burd, M., Klug, M. G., Kerbeshian, J., & Popova, S. (2019). Comorbidity and intellectual disability. In J. L. Matson (Ed.), Handbook of intellectual disabilities: Integrating theory, research, and practice (pp. 121–137). Springer International Publishing. https://doi.org/10.1007/978-3-030-20843-1_8
Fabio, R. A. (2005). Dynamic assessment of intelligence is a better reply to adaptive behavior and cognitive plasticity. The Journal of General Psychology, 132, 41–64. https://doi.org/10.3200/GENP.132.1.41-66
Fisher, M. H., Lense, M. D., & Dykens, E. M. (2016). Longitudinal trajectories of intellectual and adaptive functioning in adolescents and adults with Williams syndrome. Journal of Intellectual Disability Research, 60, 920–932. https://doi.org/10.1111/jir.12303
Flanagan, D. P., McDonough, E. M., & Kaufman, A. S. (2022). Contemporary intellectual assessment: Theories, tests, and issues. Guilford Publications.
Gathercole, S. E., Briscoe, J., Thorn, A., Tiffany, C., & ALSPAC Study Team (2008). Deficits in verbal long-term memory and learning in children with poor phonological short-term memory skills. Quarterly Journal of Experimental Psychology, 61, 474–490. https://doi.org/10.1080/17470210701273443
Giuliani, F., & Schenk, F. (2015). Vision, spatial cognition and intellectual disability. Research in Developmental Disabilities, 37, 202–208. https://doi.org/10.1016/j.ridd.2014.11.015
Greenspan, S., Harris, J. C., & Woods, G. W. (2015). Intellectual disability is “a condition, not a number”: Ethics of IQ cut-offs in psychiatry, human services and law. Ethics, Medicine and Public Health, 1, 312–324. https://doi.org/10.1016/j.jemep.2015.07.004
Greenspan, S., & Woods, G. W. (2014). Intellectual disability as a disorder of reasoning and judgement: The gradual move away from intelligence quotientceilings. Current Opinion in Psychiatry, 27, 110–116. https://doi.org/10.1097/YCO.0000000000000037
Jacquemot, C., & Scott, S. K. (2006). What is the relationship between phonological short-term memory and speech processing? Trends in Cognitive Sciences, 10, 480–486. https://doi.org/10.1016/j.tics.2006.09.002
Knox, M. (2000). Family control: The views of families who have a child with an intellectual disability. Journal of Applied Research in Intellectual Disabilities, 13, 17–28. https://doi.org/10.1046/j.1468-3148.2000.00001.x
Lifshitz, H., Shtein, S., Weiss, I., & Vakil, E. (2011). Meta‐analysis of explicit memory studies in populations with intellectual disability. European Journal of Special Needs Education, 26, 93–111. https://doi.org/10.1080/08856257.2011.543535
Lima-Rodríguez, J. S., Baena-Ariza, M. T., Domínguez-Sánchez, I., & Lima-Serrano, M. (2018). Intellectual disability in children and teenagers: Influence on family and family health. Systematic review. Enfermeria Clinica, 28, 89–102. https://doi.org/10.1016/j.enfcli.2017.10.005
Luckasson, R., & Schalock, R. L. (2015). Standards to guide the use of clinical judgment in the field of intellectual disability. Intellectual and Developmental Disabilities, 53, 240–251. https://doi.org/10.1352/1934-9556-53.3.240
Maulik, P. K., Mascarenhas, M. N., Mathers, C. D., Dua, T., & Saxena, S. (2011). Prevalence of intellectual disability: a meta-analysis of population-based studies. Research in Developmental Disabilities, 32, 419–436. https://doi.org/10.1016/j.ridd.2010.12.018
McGrew, K., & Evans, J. (2023). Internal and external factorial extensions to the Cattell-Horn-Carroll (CHC) theory of cognitive abilities: a review of factor analytic research since Carroll’s seminal 1993 treatise. Carroll Human Cognitive Abilities (HCA) Project Research Report.
McGrew, K. S., Schneider, W. J., Decker, S. L., & Bulut, O. (2023). A psychometric network analysis of CHC intelligence measures: Implications for research, theory, and interpretation of broad CHC scores “beyond g”. Journal of Intelligence, 11, 19. https://doi.org/10.3390/jintelligence11010019
McGrew, K. S., & Wendling, B. J. (2010). Cattell-Horn-Carroll cognitive-achievement relations: What we have learned from the past 20 years of research. Psychology in the Schools, 47, 651–675. https://doi.org/10.1002/pits.20497
McKenzie, K., Milton, M., Smith, G., & Ouellette-Kuntz, H. (2016). Systematic review of the prevalence and incidence of intellectual disabilities: Current trends and issues. Current Developmental Disorders Reports, 3, 104–115. https://doi.org/10.1007/s40474-016-0085-7
Melby-Lervåg, M., Lyster, S. A. H., & Hulme, C. (2012). Phonological skills and their role in learning to read: a meta-analytic review. Psychological Bulletin, 138, 322–352. https://doi.org/10.1037/a0026744
Memisevic, H., & Sinanovic, O. (2013). Executive functions as predictors of visual-motor integration in children with intellectual disability. Perceptual and Motor Skills, 117, 913–922. https://doi.org/10.2466/15.25.PMS.117x25z4
Mervis, C. B., Kistler, D. J., John, A. E., & Morris, C. A. (2012). Longitudinal assessment of intellectual abilities of children with Williams syndrome: Multilevel modeling of performance on the Kaufman Brief Intelligence Test – second edition. American Journal on Intellectual and Developmental Disabilities, 117, 134–155. https://doi.org/10.1352/1944-7558-117.2.134
Odom, S. L., Horner, R. H., & Snell, M. E. (2009). Handbook of developmental disabilities. Guilford Publications.
Ozkan, M., Senel, S., Arslan, E. A., & Karacan, C. D. (2012). The socioeconomic and biological risk factors for developmental delay in early childhood. European Journal of Pediatrics, 171, 1815–1821. https://doi.org/10.1007/s00431-012-1826-1
Pellegrini, A. D. (2001). Practitioner review: The role of direct observation in the assessment of young children. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 42, 861–869. https://doi.org/10.1111/1469-7610.00783
Sajewicz-Radtke, U., Jurek, P., Olech, M., Łada-Maśko, A. B., Jankowska, A. M., & Radtke, B. M. (2022). Heterogeneity of cognitive profiles in children and adolescents with mild intellectual disability (MID). International Journal of Environmental Research and Public Health, 19, 7230. https://doi.org/10.3390/ijerph19127230
Sajewicz-Radtke, U., Łada-Maśko, A., Olech, M., Jurek, P., Bieleninik, Ł., & Radtke, B. M. (2025a). As sociation between parental education level and intelligence quotient of children referred to the mental healthcare system: a cross-sectional study in Poland. Scientific Reports, 15, 4142. https://doi.org/10.1038/s41598-025-88591-3
Sajewicz-Radtke, U., Łada-Maśko, A., Olech, M., Leoniak, K. J., & Radtke, B. M. (2025b). Declarative memory profiles in children with non-specific intellectual disability: a cluster analysis approach. Frontiers in Psychiatry, 16, 1581144. https://doi.org/10.3389/fpsyt.2025.1581144
Schalock, R. L., Luckasson, R., & Tassé, M. J. (2021). An overview of intellectual disability: Definition, diagnosis, classification, and systems of supports (12th ed.). American Journal on Intellectual and Developmental Disabilities, 126, 439–442. https://doi.org/10.1352/1944-7558-126.6.439
Schneider, W. J., & McGrew, K. S. (2018). The Cattell-Horn-Carroll theory of cognitive abilities. In M. Flanagan (Ed.), Contemporary intellectual assessment: Theories, tests, and issues (pp. 73–163). Guilford Press.
Schwartz, R. G. (2017). Handbook of child language disorders (2nd ed.). Taylor & Francis. Sermier Dessemontet, R., Moser Opitz, E., & Schnepel, S. (2020). The profiles and patterns of progress in numerical skills of elementary school students with mild and moderate intellectual disability. International Journal of Disability, Development and Education, 67, 409–423. https://doi.org/10.1080/1034912X.2019.1608915
Singh, N. N. (2016). Handbook of evidence-based practices in intellectual and developmental disabilities. Springer International Publishing.
Sitnik-Warchulska, K., Izydorczyk, B., & Lipowska, M. (2019). Clinical psychological diagnosis in children and adolescents: Challenges and recommendations of consultants in clinical psychology. Psychiatria i Psychologia Kliniczna, 19, 54–62. https://doi.org/10.15557/PiPK.2019.0008
Stigen, L., Bjørk, E., & Lund, A. (2023). The power of observation.Occupational therapists’ descriptions of doing observations of people with cognitive impairments in the context of community practice. Scandinavian Journal of Occupational Therapy, 30, 21–33. https://doi.org/10.1080/11038128.2020.1839966
Tassé, M. J., Luckasson, R., & Schalock, R. L. (2016). The relation between intellectual functioning and adaptive behavior in the diagnosis of intellectual disability. Intellectual and Developmental Disabilities, 54, 381–390. https://doi.org/10.1352/1934-9556-54.6.381
Tassé, M. J., Schalock, R. L., Balboni, G., Bersani, H., Jr., Borthwick-Duffy, S. A., Spreat, S., Thissen, D., Widaman, K. F., & Zhang, D. (2012). The construct of adaptive behavior: Its conceptualization, measurement, and use in the field of intellectual disability. American Journal on Intellectual and Developmental Disabilities, 117, 291–303. https://doi.org/10.1352/1944-7558-117.4.291
Vandereet, J., Maes, B., Lembrechts, D., & Zink, I. (2011). Expressive vocabulary acquisition in children with intellectual disability: Speech or manual signs? Journal of Intellectual and Developmental Disability, 36, 91–104. https://doi.org/10.1080/13668250.2011.572547
Whitaker, S. (2008). The stability of IQ in people with low intellectual ability: an analysis of the literature. Intellectual and Developmental Disabilities, 46, 120–128. https://doi.org/10.1352/0047-6765(2008)46 [120:TSOIIP]2.0.CO;2
World Health Organization (2019). International statistical classification of diseases and related health problems (11th ed.). Retrieved from https://icd.who.int/
Xiaoming, X. (2010). How do we go about investigating test fairness? Language Testing, 27, 147–170. https://doi.org/10.1177/0265532209349465
Yang, Q., Yang, J., Zheng, L., Song, W., & Yi, L. (2021). Impact of home parenting environment on cognitive and psychomotor development in children under 5 years old: a meta-analysis. Frontiers in Pediatrics, 9, 658094. https://doi.org/10.3389/fped.2021.658094
