“Theory of mind” is a broad and multifaceted construct (Astington & Baird, 2005) that is often used interchangeably with the terms “perspective-taking,” “metacognition,” and “social cognition” (Hutchins, Prelock, & Bonazinga, 2011). Research in theory of mind has been extremely active over the last 30 years and a wide variety of theory of mind tests have been developed. Notably, traditional measures have relied almost exclusively on direct assessment of child performance. As a result, the child’s cognitive and language level can influence performance so as to obscure (or artificially credit) theory of mind knowledge.  Moreover, motivational factors (e.g., interest level, fatigue, attention) often operate in the assessment of young children and individuals with a wide variety of clinical conditions (e.g., autism, attention-deficit, sensory loss, learning disability). Undoubtedly, professionals working with young children and individuals with disabilities will be familiar with a variety of assessment challenges when respondents lack motivation to participate in testing procedures. Motivational challenges may be compounded by a variety of situational factors that can also impede task performance. These include, but are by no means limited to, a lack of understanding of the pragmatics of the assessment situation, unfamiliarity with persons administering the test, and frustration during difficult tasks.

Another drawback associated with traditional measures of theory of mind is that ceiling effects are common when social cognitive understanding is relatively good. This has led to the development of several advanced theory of mind tests (e.g., Baron-Cohen, Wheelright, Hill, Raste, & Plumb, 2001; Happé,1994). Although these advanced measures are innovative methods for assessing theory of mind in individuals with high functioning autism and Asperger syndrome,

“interest in people with high-functioning autism can obscure the fact that most people with the disorder have moderate to severe learning difficulties. In classic autism this may be about 75%, and more than half of those affected develop no appreciable language. This means that theory of mind deficits in autism have only been examined in a fraction of sufferers; typically experiments include only children with verbal mental ages of above 4 years” (Doherty, 2009, p.179).

Finally, the explicit nature of many traditional theory of mind tasks are quite unlike the ways that real life social dilemmas are presented (e.g., Hutchins et al., 2011). In fact, the notion that task performance can exceed social cognitive functioning when it is applied in everyday life has been the topic of considerable concern. This raises important issues about the social validity of theory of mind assessment.

The Theory of Mind Inventory (ToMI) represents a new method for assessing theory of mind that addresses the limitations of traditional theory of mind measures. This well-validated caregiver-informant measure is designed to assess a wide range of theory of mind competencies, it does not suffer from ceiling effects when administered to individuals with ASD, and it is not vulnerable to test-practice effects and child linguistic, cognitive, and motivational factors.