Neurodevelopmental diagnoses rebound after pandemic disruptions

A population-based cohort study in JAMA Network Open found that rates of new neurodevelopmental diagnoses among children aged 6 years or younger declined sharply at the onset of the COVID-19 pandemic, then rebounded and increased in the postpandemic period.¹ The findings suggest that early disruptions in access to care may have delayed identification, with implications for pediatric screening and referral practices.

Changes in the ways children learned and developed were reported during the COVID-19 pandemic.² To assess developmental trends, investigators analyzed administrative health data from Ontario, Canada, spanning March 2015 through December 2024.¹ Across more than 1.4 million children at risk, 291,896 received a new neurodevelopmental diagnosis during the study period. Conditions included autism spectrum disorder and developmental delays, identified using physician billing codes.

“Although prenatal exposure to SARS-CoV-2 infection has not been consistently associated with neurodevelopmental sequelae, emerging evidence suggests that such exposure, as well as pandemic-related changes to early life experiences, may be associated with neurodevelopmental delays,” wrote investigators.

Population-based trends in diagnosis rates

The retrospective cohort study used interrupted time series analysis to compare diagnosis rates across prepandemic, pandemic, and postpandemic periods. A new diagnosis required 2 physician visits at least 30 days apart. Monthly rates were calculated per 1000 child-months.

During the prepandemic period, diagnosis rates increased steadily over time, with a monthly slope of 0.04 (95% CI, 0.03-0.05; P < .001). At the onset of the pandemic in March 2020, rates dropped significantly by 0.91 per 1000 child-months compared with expected trends (95% CI, −1.56 to −0.25; P = .01).

Rates stabilized during the pandemic without significant change in slope (0.03; 95% CI, −0.002 to 0.06; P = .07). In the postpandemic period, however, diagnosis rates resumed a significant upward trend (slope 0.03; 95% CI, 0.02-0.04; P < .001). Overall rates increased from 2.8 per 1000 child-months prepandemic to 3.6 during the pandemic and 4.1 postpandemic.

Boys consistently had higher diagnosis rates than girls across all periods, though trends over time were similar by sex. Infants aged 12 months or younger had the lowest rates, while children older than 12 months accounted for the majority of diagnoses.

The timing of diagnosis also shifted. The median interval from initial visit to diagnosis increased from 4.4 months prepandemic to 5.2 months during the pandemic and 5.4 months postpandemic, suggesting delays in assessment or follow-up.

Clinical implications for screening and access

The observed drop in diagnoses early in the pandemic likely reflects reduced access to in-person care and developmental assessment, as outpatient services shifted to virtual formats or closed temporarily. These findings align with broader disruptions in pediatric preventive care during this period.

The subsequent increase in diagnosis rates may represent both recovery of delayed cases and continued underlying growth in neurodevelopmental conditions. Prior estimates suggest that up to 24% of publicly insured children in the United States receive a neurodevelopmental diagnosis by the age of 8 years.

Additionally, the study highlights the resilience of diagnostic trends over time. Despite the initial disruption, long-term slopes in diagnosis rates did not differ significantly between periods, suggesting a return to baseline patterns of identification.

“Although our findings are reassuring, system backlogs and long wait times may obscure true neurodevelopmental diagnostic rates in the pandemic and postpandemic periods,” wrote investigators.

References

1. Freeman SJ, Nisenbaum R, Sgro MD. Neurodevelopmental diagnoses before, during, and after the COVID-19 pandemic. JAMA Netw Open. 2026;9(4):e265683. doi:10.1001/jamanetworkopen.2026.5683
2. Araújo LA, Veloso CF, Souza MC, Azevedo JMC, Tarro G. The potential impact of the COVID-19 pandemic on child growth and development: a systematic review. J Pediatr (Rio J). 2021;97(4):369-377. doi:10.1016/j.jped.2020.08.008