“…While DSM-IV criteria stipulate that ADHD symptoms must be present across different conditions it is clear, as noted above, that situational factors influence behavior and may in part account for some of the variance between parent and teacher reports of ADHD symptoms. For example, performance tends to be poorer in the afternoon compared to the morning (Dane, Schachar, & Tannock, 2000;Porrino et al, 1983); under low levels of stimulation (Antrop, Roeyers, Van Oost, & Buysse, 2000); when task complexity taxes organizational abilities (Douglas, 1983); and when restraint is required (Barkley & Ullman, 1975;Luk, 1985). Behavioral problems are far more likely to emerge when a child must persist in a work-related task (e.g., homework, household chore) or in a setting that constrains their behavior (e.g., church, restaurant) than in unrestricted, free play situations (Barkley & Edelbrock, 1987;Breen & Altepeter, 1990).…”