During a community camp, a multidisciplinary team evaluates several children…

Concept: screening versus confirmatory assessment

Disability identification proceeds in two distinct stages. A screening tool is a broad first-level instrument, usually completed by a teacher or field worker, and it may cover several disability domains at once; it flags a child as “at risk” and generates a referral. A confirmatory (diagnostic) tool is a standardised, professionally administered battery built for one specified condition, whose subtests sample the exact skill areas that define that condition; the diagnosis is then established by the professional on the basis of that battery together with clinical evaluation and the exclusion of alternative causes. So the two questions to ask of any instrument are which stage of identification it belongs to and, for a confirmatory instrument, which single condition it is built for.

Applying this to the case

The stem states that the child is already suspected of Specific Learning Disability, so the flagging stage is over and what is required is the confirmatory instrument for that particular domain. Specific Learning Disability is defined by deficits in reading, writing, spelling and arithmetic despite adequate intelligence and schooling, so the confirming instrument must sample exactly those skills. The NIMHANS battery for SLD assessment, developed at the National Institute of Mental Health and Neurosciences, Bengaluru, is that instrument: it is professionally administered, has age-graded levels, and its subtests cover attention, reading, writing, spelling, comprehension, arithmetic, visual-motor ability and memory, yielding a skill-wise diagnostic profile.

Cross-check against the other instruments

• DEGSN checklist for intellectual disability: a checklist that screens and tentatively categorises disability, anchored to the intellectual disability domain rather than to reading, writing and arithmetic skills.

• BERA test for hearing impairment: Brainstem Evoked Response Audiometry records the electrical response of the auditory nerve and brainstem to sound stimuli and maps the hearing pathway.

• PRASHAST Part 2 for at-risk children: NCERT's Pre-Assessment Holistic Screening Tool, whose Parts 1 and 2 are first- and second-level school screening steps that facilitate referral for further diagnosis.

Only a professionally administered diagnostic battery built around the reading, writing and arithmetic skill set can confirm Specific Learning Disability, which is why the NIMHANS battery for SLD assessment is the appropriate tool at this stage.