Mental age and intellectual disability: Psychologists' perspectives on the use of the term ‘mental age’ as it relates to adults with an intellectual disability

Despite the growing international move away from the term ‘mental age’, the term continues to be used in some settings with adults with an intellectual disability. Arguably, the construct of ‘mental age’ conflicts with current rights-based approaches yet its continued use suggests that it may have certain utilities. This study aimed to explore the use of the construct of mental age in the context of supporting adults with an intellectual disability in Ireland, and its perceived value and limitations in clinical practice. Forty-three psychologists in Ireland responded to a 10-item online survey using a mix of closed and open-ended questions. Descriptive statistics were used and analysis was informed by reflexive thematic analysis. Twenty of the 43 respondents reported that mental age continues to be used in clinical practice. Analysis was informed by reflexive thematic analysis and identified five main themes: (1) negative connotations, (2) inconsistent with best practice, (3) supporting the person with an intellectual disability, (4) communicating about the person with intellectual disability and (5) moving on from mental age. The findings suggest that this construct is considered problematic and limited in its meaning and while there is a desire for change, there are challenges in finding an alternative method of communicating information about ability in a brief and easily understood way.