Refining diagnoses: applying the DC-LD to an Irish population with intellectual disability.
Re-checking old charts with the DC-LD manual revealed seven new psychiatric diagnoses in adults with moderate to profound ID.
01Research in Context
What this study did
A team in Ireland pulled 113 adult charts from a large residential center. Every adult had moderate to profound intellectual disability.
Two clinicians re-coded each chart with the DC-LD, a UK manual that gives exact rules for psychiatric and behavior labels. No new tests were run; they simply scored what was already written.
What they found
Seven adults picked up brand-new psychiatric diagnoses such as depression or psychosis. Problem behaviors like self-injury now had formal DC-LD labels instead of vague notes.
Still, a large share of the group ended up in the 'unspecified' bucket. The tool added clarity, but most cases stayed general.
How this fits with other research
Tarasova et al. (2024) later did the same kind of check-up with the DSQIID-G for dementia in German adults with ID. Both studies show that giving clinicians a clear rulebook finds hidden conditions.
Mulder et al. (2020) trimmed and re-scored the SCQ and SRS-2 for fragile-X syndrome. Like the DC-LD work, tighter item rules boosted diagnostic accuracy, proving the wider point: manuals matter.
van Schrojenstein Lantman-de Valk et al. (2006) looked at family stress, not labels, and found autism plus ID created the worst behavior profiles. Their data remind us that clearer diagnosis (what DC-LD offers) can guide the extra support those families need.
Why it matters
If you serve adults with moderate to profound ID, a one-hour chart review with the DC-LD can surface treatable mental-health issues that risk being blamed on 'the disability.' You do not need new tests or consent meetings—just the manual and highlighter. Start with clients whose behaviors recently changed or who have vague 'unspecified' notes; those charts are the low-hanging fruit for new diagnoses and better treatment plans.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Pick one adult chart labeled 'unspecified behavioral disorder' and re-score it with the free DC-LD criteria—see if a treatable diagnosis appears.
02At a glance
03Original abstract
BACKGROUND: The diagnostic criteria for psychiatric disorders for use with adults with learning disabilities/mental retardation (DC-LD) is a diagnostic tool developed in 2001 to improve upon existing classification systems for adults with learning disability. The aim of this study was to apply the classification system described by the DC-LD to a residential intellectual disability (ID) population to examine whether it improved our diagnostic understanding of residents. METHODS: Chart reviews of 113 of 178 people in a residential ID service were conducted. For each resident, information was recorded according to the DC-LD multi-axial system. Each resident's case was then discussed with a member of nursing staff familiar with the resident. If diagnosis was unclear, the case was discussed with a senior clinical psychiatrist. RESULTS: The percentage of residents with a moderate to profound ID was 87.6%. In total, 94 diagnoses of psychiatric illness (Axis III, Level B, DC-LD) were made. Of those 94 diagnoses, seven new diagnoses were found because of DC-LD criteria. Of the total number of psychiatric diagnoses made, 72.3% were non-specific, residual category diagnoses. A total of 79 residents (69.9%) had at least one behaviour problem diagnosed on Axis III, Level D, Problem behaviours. Fifty-six (49.6%) of residents in this sample had co-morbid epilepsy. CONCLUSIONS: In people with moderate to profound learning disabilities, diagnosis continues to be challenging. The DC-LD is a useful tool in helping to clarify diagnoses in this population by providing revised criteria and a system to classify problem behaviours. The DC-LD would be more helpful if specific axes were included to document medical and psychosocial problems independently from other diagnoses. Further research is warranted to determine whether the DC-LD hierarchical approach to diagnosis improves diagnostic validity.
Journal of intellectual disability research : JIDR, 2005 · doi:10.1111/j.1365-2788.2005.00760.x