For the interviewer-administered 36-item version of the WHODAS 2.0, the interviewer elicits difficulties the respondent has because of health conditions. The respondent is asked to consider all conditions present: diseases, illnesses, or other health problems of any duration; injuries; mental or emotional problems; and problems with alcohol or drugs. The interviewer elicits whether over the past 30 days the respondent has had difficulty with a given activity as demonstrated by the need for increased effort, the experience of discomfort or pain, slowness, or changes in the way the interviewee does an activity. The respondent is encouraged to consider these difficulties for activities performed as he or she usually does the activity. These key foci are also presented on a flashcard so that the respondent can read the instructions as well as listen to the interviewer speak them. A second flash card is presented to the respondent, and the interviewer encourages the respondent to use the following scale when responding: none, mild, moderate, severe, extreme or cannot do. Both flashcards remain present throughout the interview so that the respondent can refer to them at will.

The WHODAS 2.0 scoring can occur through a simple summing and averaging of scores, which may be desirable in fast-paced clinical settings. There is also a computerized scoring option available that uses item-response theory to weight the 36 items based upon normative data in order to present a more precise summary score reflecting the level of disability [10].

An obvious dilemma facing respondents using the five-point scale to describe how much difficulty they have experienced in the past 30 days is that the severity levels are not operationalized in any way to encourage consistency across respondents. The extreme or cannot do choices may be clear enough, but what are the finer distinctions between mild, moderate, and severe? This dilemma is reminiscent of our earlier discussion of DSM-IV-TR disability severity as it related to the Global Assessment of Functioning, which is no more. Added complexity arrives from asking the respondents to select these levels of difficulty without adequate distinctions between severity levels.

If the clinician is making the assessment, perhaps a metric can be developed that links to commonly administered objective psychological tests so that rating the domains is more consistent across evaluations. Or perhaps further clarification can be added to the second card to help respondents reply on a more consistent metric.

Employing the WHODAS 2.0 within the DSM-5 highlights another important limitation; notwithstanding the list of objective psychological testing domains in Table 14.1 that are available, current limitations in psychological measurement mean that many psychiatric diagnoses lack reliable measures of severity to inform the use of the WHODAS 2.0. Despite our best efforts, in many cases the clinical significance of a psychiatric diagnosis remains a matter of clinical judgment as to whether “the disturbance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning” [2, p. 21].