Brief Symptom Inventory symptom profiles of outpatients with borderline intellectual functioning and major depressive disorder or posttraumatic stress disorder: Comparison with patients from regular mental health care and patients with Mild Intellectual Disabilities.
Adults with borderline intellectual functioning say they feel less depressed than other clients, so double-check low scores before you rule depression out.
01Research in Context
What this study did
The team gave the Brief Symptom Inventory to three outpatient groups.
Group one had borderline intellectual functioning plus major depression.
Group two had BIF plus PTSD.
Group three was regular mental-health outpatients.
They compared the symptom scores to see who reported more distress.
What they found
BIF clients with depression scored lower on every BSI scale than regular clients.
The BIF-PTSD group looked about the same as the regular group.
All other differences were tiny.
In plain words, BIF clients said they felt less sick than typical clients, but only if they had depression.
How this fits with other research
Jackson et al. (2025) built on this work. They made a short PTSD screener for the same BIF-MID adults. Their tool lets you move from "interesting profile" to "quick screen" in one step.
Dinya et al. (2012) looked at Hungarian teens with dual diagnosis. They also saw that lower IQ linked to higher behavior scores. Together the two studies show the pattern holds across age and country.
Golubović et al. (2013) found teens with ID and their parents disagreed on quality-of-life ratings. That warns us: self-report from people with ID can differ from proxy report, just like Jannelien’s milder depression scores.
Why it matters
If you assess adults with BIF, expect them to under-report depression symptoms. Do not take low BSI scores at face value. Pair the inventory with caregiver input or direct observation. When PTSD is the concern, grab the new TS-ID screener from Jackson et al. (2025) and use the adult self-report cut-off of 18. These steps stop you from missing real distress that the client cannot describe.
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02At a glance
03Original abstract
INTRODUCTION: In most countries, people with borderline intellectual functioning (BIF) are not considered a separate group in mental health care. There is little to no research on the impact of BIF on the presentation, nature and severity of mental health problems. The aim of the present exploratory study was to compare, in a naturalistic setting of patients referred to secondary care, symptom profiles of patients with BIF diagnosed with either major depressive disorder (MDD) or posttraumatic stress disorder (PTSD) to patients from regular mental health care (RMHC) and patients with Mild ID diagnosed with the same disorders. METHODS: We used a cohort of adolescent and adult outpatients (aged 16-88) with or without BIF diagnosed with a primary diagnosis MDD or PTSD. Primary outcome was the nature and severity of psychopathological symptoms assessed at baseline using the Brief Symptom Inventory. All outcomes were adjusted for gender and age. RESULTS: Results showed that BIF patients with a primary diagnosis MDD reported less severe symptoms on BSI Total and the subscales Depression, Obsession-Compulsion and Psychoticism than patients from regular mental health care (RMHC). There were no statistically significant differences in reported symptom severity on BSI Total and the different BSI subscales between BIF patients with PTSD and either patients from RMHC or patients with Mild ID. Patients Mild ID, did report significantly less severe symptoms on the subscale Depression and on the subscale Psychoticism than patients from RMHC. DISCUSSION: Since there were no other published studies into symptom profiles in patients with BIF compared to either patients with higher or lower levels of cognitive functioning, the study was mainly exploratory in nature, providing direction for future research. Results indicate that symptom profiles did not widely differ, but that there might be some characteristics unique to patients BIF separating them as a group from both patients from RMHC and patients with Mild ID.
Research in developmental disabilities, 2016 · doi:10.1016/j.ridd.2016.01.007