An exploratory factor analysis of HONOS-LD scales

Purpose The purpose of this study is to identify clinically meaningful groups of Health of the Nation Scales Learning Disabilities (HONOS-LD) single-item scales that might be used as short scales that are more reliable than single-item scale scores and more focused than the sum of scale scores. The single-item scales are likely to be unreliable in many applications. The sum of scale scores is a heterogeneous measure that is not a good representative of any specific difficulties that people who have intellectual disabilities may have and the effects of interventions on any specific difficulties may be masked by fluctuations in the ratings of other scales. Design/methodology/approach A total of 2,109 pseudonymised complete HONOS-LD ratings were factor-analysed using principal factor extraction and oblimin rotation. Three-, four- and five-factor rotated patterns were examined. Findings Three factors that each have three or more strong loadings (≥|0.50|) were identified that jointly included 11 single-item scales: one representing problems with cognitive competencies, one representing depressive phenomena or other mood problems and one representing problems with social competencies. A weaker factor that represents behaviour that challenges services is indicated; it includes five single-item scales. Both the cognitive competencies and social competencies groups of items were also reported in a previous study by Skelly and D’Antonio (2008) and may be stable. The present study’s factor representing behavioural difficulty has some similarity to Skelly and D’Antonio’s “functional behaviour and attachment disturbance” group. In other respects, the present study and the previous study differ. Research limitations/implications The outcomes of these factor analyses indicate that some of the single-item scales can be combined into groups. However, the specific groups found in this study must be regarded as possibly unstable because of the likelihood of weak inter-rater reliability in HONOS-LD data and differences between this analysis and Skelly and D’Antonio’s. Further research is needed to support or modify them. Practical implications The cognitive competence and social competence groups of items may be used as subscales if they are convenient. The groups representing mood and behavioural problems should be supported by further research before being used. Originality/value This is the second published factor analysis of the HONOS-LD and includes a much larger data set than the first. It has some similarities to and differences from the first and is a further step in the process of identifying useful groupings of HONOS-LD single-item scales.