| Developmental Screening Session | Diagnostic Assessment | |
|---|---|---|
| Question it answers | “Is there enough concern to look deeper?” | “What is the diagnosis (if any), how significant is it, and what supports are needed?” |
| Purpose | Quickly identify whether a child is at risk for a developmental delay or condition and needs further evaluation. | Determine whether a diagnosis is present, define the child’s developmental profile, and guide individualized intervention. |
| Activities | Brief, broad check of key domains (communication, motor, social, problem-solving, play, self-help skills). May include condition-specific screeners (e.g., risk areas) Parents share concerns and complete questionnaires guided by the clinician. | Comprehensive, multi-domain evaluation (medical, developmental, cognitive, language/communication, adaptive, social-emotional, behavior), plus differential diagnosis. Parents provide an in-depth history and participate in a structured interview. Consent for sharing records with other team members (e.g., physician/psychologist for diagnosis). |
| Professional / Provider | Trained frontline providers (e.g., family physicians, paediatricians) often with input from caregivers. Licensed clinicians trained in diagnosis (e.g., developmental paediatricians/child psychiatrists, psychologists, SLPs, behaviour analysts, with others contributing domain-specific testing and reports). | Licensed clinicians trained in diagnosis (e.g., developmental paediatricians, physicians, child psychiatrists, psychologists; other regulated health professionals specifically trained in the tools with others contributing (e.g., SLPs/OTs/behaviour analysts contribute domain-specific testing and reports). |
| Location | Physician’s office, community clinics, child-care/early years settings, private practices, virtual formats. | Specialty clinics, hospital programs, psychology practices, multidisciplinary teams. |
| Length of time | Very brief: typically 15–30 minutes including scoring. | Lengthy: typically 2–6+ hours across 1–3 visits (interviews, testing, observation, feedback). |
| Tools typically used (examples) | Parent questionnaires and brief screeners (e.g., LookSee development screeners; Communication Matrix, direct observation). | Standardized diagnostic and developmental tools (e.g., M-CHAT, ADOS-2, ADI-R, verbal behaviour screener, standardized language tests), clinical interview, DSM-5-TR/ICD criteria, medical review. |
| Information obtained | Risk status (e.g., “typical,” “monitor,” “refer”). Not a diagnosis. | Diagnostic formulation (e.g., autism, language disorder, etc.), severity/level of support, strengths/needs, and a written report with recommendations. |
| Accuracy | High sensitivity – catch most who need follow-up evaluation Some false positives – monitor or return in the future Not definitive. | Higher specificity and precision; integrates multiple sources to minimize false positives/negatives; definitive for clinical decision-making. |
| Next steps | Negative screen → routine monitoring Positive/concern → referral for diagnostic assessment or targeted evaluation. | Feedback session, referrals to services (e.g., SLP, OT, ABA, mental health), treatment/education plan, eligibility documentation for supports. |
| How often | Universal at key ages (e.g., 18-month physician visit) and any time a concern arises (e.g., after 18-months, at school entry, during early elementary school). | On an ‘as needed basis’ where there are concerns or to confirm/clarify a condition; may be repeated for re-evaluation or transition planning. |
| Costs | Usually low/no cost; often built into routine care or community programs (e.g., 18-month well-baby visit with the paediatrician). | Higher cost; may have waitlists; may require a physician’s referral (but not always the case if obtained privately) |
| When to choose | Use for early detection | Use to confirm or rule out conditions, plan interventions, and establish service eligibility. |