NOCC Reporting Criteria

An important issue in the analysis and reporting of the NOCC measures is to determine when a measure is ‘valid’ with respect to the clinical ratings provided.

Outcome measures such as the HoNOS family are referred to here as measures (elsewhere, these have been variously referred to as scales, instruments). Some measures comprise multiple components, such as items (these have been variously referred to as scales). Items can be aggregated into subscales and total scores (these have been variously referred to as summary and total scores). Ratings of items can be described in terms of three mutually exclusive categories:

1. valid ‘clinical’ ratings that typically indicate levels of problem severity;

2. valid ‘non-clinical’ ratings that typically indicate reasons why problem severity was not rated; and

3. invalid values such as ‘nulls’ or values outside of the range for 1 and 2 above.

The validity of a measure is derived from consideration of the validity of the items that comprises that measure. Valid scores can be estimated either when all of the items are clinically valid OR when a sufficient number of items are clinically valid. Two issues to consider are:

1. How many items need to have a valid clinical rating in order for the overall measure to be considered valid?

2. If one or more of the items does not have a valid clinical rating, how does this impact on the scoring of subscale and total scores?

The following table shows the criteria used to determine whether a NOCC measure had been validly completed for the purposes of subsequent statistical reporting: