This article has supplementary material on the web site: www.jdbp.org.
Index terms: Well-baby visit, developmental screening, developmental delay, pediatrics
ABSTRACT
Objective:
We sought to measure whether receipt of an enhanced 18-month well-baby visit with use of a developmental screening tool versus a routine 18-month well-baby visit (which typically involves developmental surveillance without screening) is associated with time to identification of developmental delays.
Method:
We conducted a cohort study of children (17–22 months) in Ontario who received an 18-month well-baby visit (March 2020‒March 2022), followed to September 2022 using linked health administrative datasets. Visits were categorized as enhanced (n = 83,554) or routine (n = 15,723). The outcome was the identification of a developmental delay within 6 months (early) and more than 6 months after (late) the 18-month visit. Piecewise Cox proportional hazards models estimated hazard ratios (aHR) adjusted for child, maternal, and physician factors, comparing developmental delay diagnosis by visit type.
Results:
Children who received an enhanced visit were slightly older, had a lower representation in the most deprived group, and a higher percentage of patients with pediatricians as their usual provider of care. After adjustment, children with enhanced compared with routine visits were more likely to have developmental delays detected in the early period (aHR 1.19 95% CI 1.11‒1.28) but not in the late period following the well-baby visit.
Conclusion:
Enhanced visits are associated with earlier identification of developmental delays compared with routine visits in the 6 months following the 18-month well-baby visit. Enhanced developmental monitoring using screening tools may facilitate earlier recognition of developmental concerns.
INTRODUCTION
Developmental delays are defined as slowed progression through predictable motor, speech/language, cognitive and social/emotional developmental phases, resulting in not reaching expected milestones.1 Although developmental delays may persist throughout life and ultimately are identified as a developmental disorder, most children will progress to meet developmental milestones, especially with early intervention.2 The American Academy of Pediatrics and the Canadian Paediatric Society both recommend routine developmental surveillance by the child's primary care physician, to monitor infant and child development and ensure the timely identification of developmental concerns.3
In Canada, well-baby care is routinely provided with at least 6 recommended well-baby visits scheduled before age 2 years.4 Well-baby visits typically involve developmental surveillance, as well as other preventative care and anticipatory guidance.4 In particular, the 18-month well-baby visit is an important time to assess a child's developmental progress, as children should reach many critical developmental goals such as pointing to show something of interest, gesturing, learning words and short phrases, and climbing by that age.5 An enhanced 18-month well-baby visit includes the components of a routine well-baby checkup and has an added required element of a developmental screen. The enhanced visit also offers an opportunity to provide a referral to specialized services for children who require it.6
Developmental screening (as used in an enhanced well-baby visit but not a routine well-baby visit) refers to the use of standardized tools (caregiver or clinician completed) to identify risks for developmental delay. Screening can be targeted (for children who are identified as high risk) or universal (for children who do not show any apparent signs of developmental delay, or whose caregivers or clinicians have no concerns about development).7 Standardized developmental screening tools, such as the Nipissing District Developmental Screen (a tool completed by parents and used to assess child development, more recently called the Looksee Checklist),5,7 facilitate screening and encourage discussion between the physician and caregiver on child development, parenting, early literacy, and available community programs and services.5,6 This differs from developmental surveillance, which refers to “the ongoing monitoring of development, identification of risk factors and elicitation of parental concerns” and can be conducted by both parents and health care providers.7
Canada's federal health care insurance legislation (the Canada Health Act) dictates that provinces and territories are required to cover medically necessary services, including well-baby visits, for eligible residents. In addition to these insured health services, the provinces and territories provide a range of other services, which often target specific population groups (such as children) and vary from 1 province to another, with different levels of funding.8 Variation exists across provinces and territories in terms of which ones incorporate formal developmental screening as part of the 18-month well-baby visit and among those who do complete the screening, where it takes place, which health professionals administer it, and which instruments that are used.9 Ontario is the only Canadian province which recommends and funds an enhanced 18-month well-baby visit covered under Ontario's universal, single-payer health insurance plan. As of 2024, the enhanced fee code is remunerated 50% to 60% higher (depending on practitioner specialty) than a routine well-baby visit, although uptake is not universal.6 A recent multicountry review of comparable universal child health systems similarly found substantial variation in developmental surveillance models across Canada, Australia, New Zealand, Sweden, and the United Kingdom, including differences in national pediatric guidance, the role of pediatricians in primary care, and the tools used for assessment.10 Despite the use of an enhanced visit in Ontario, evidence for its benefit in improving early detection of developmental delays is limited, and whether it should be used as a model for other jurisdictions remains to be determined.
Guidance on best practices regarding early developmental screening varies across authoritative bodies. The US Preventive Services Task Force recently published guidance concluding that, “current evidence is insufficient to assess the balance of benefits and harms of screening for speech and language delay and disorders in children who do not present with signs or symptoms of parent/caregiver concerns”.11 The Canadian Task Force likewise recommends against screening for developmental delay using standardized tools in children aged 1 to 4 years with no apparent signs of developmental delay and whose parents and clinicians have no concerns about development.7 In contrast, the American Academy of Pediatrics recommends developmental surveillance at each well-baby visit, with formal developmental screening at 9, 18, and 30 months.3 This study will add to the body of literature regarding health outcomes associated with screening for developmental disorders among children whose parents and clinicians have raised no concerns and whether screening results in earlier identification of developmental concerns.12
We aimed to determine whether there is a change in time to the identification of developmental delays (including, but not limited to, gross motor, fine motor, speech and language disability) among healthy children who received an enhanced compared with routine 18-month well-baby visit. We hypothesized that children who received an enhanced 18-month well-baby visit were more likely to receive an earlier developmental delay diagnosis compared with those who received a routine visit.
METHODS
Study Design and Population
We performed a population-based cohort study using linked health administrative and demographic datasets of healthy children between the ages of 17 to 22 months (born between October 31, 2018, and May 31, 2020 in an Ontario hospital), living in Ontario, Canada, who were eligible to receive an 18-month well-baby visit and followed up to at least 6 months and up to 32 months after the visit (eFig. 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510). We excluded children with missing sex or invalid birth dates; those born preterm (<37 weeks) or whose birth records were missing their gestational age; children with complex chronic conditions (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510), congenital anomalies (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510), or developmental delays (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510) identified before 17 months; children who received any care in community health centres since birth; those who had no 18 months well-baby visit (eTable 2, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510) and children who were not eligible for OHIP at 17 months (index date).
Exposure Groups
The main exposure was type of 18-month well-baby visit, defined as receipt of a routine (non-enhanced) vs an enhanced 18-month well-baby with a standardized developmental screening tool and discussion regarding healthy child development visit between 17 and 22 months.6 Routine 18-month well-baby visits were identified using family physician or pediatrician physician billing codes of A007 and A262, respectively, with an accompanying diagnostic code of 916 (well-baby care). Enhanced 18-month well-baby visits were identified using the specific billing codes for the enhanced visit A002 (family physicians) and A268 (pediatricians) (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510).
Study Outcomes
The study outcome was identification of any developmental concern in the periods of up to 6 months following the well-baby visit (early) and after 6 months following the well-baby visit (late), when children are aged 2 to nearly 4 years. This initial 6-month window following the well-baby visit captures a critical developmental period when many milestones emerge and delays are most likely to be identified and documented. We identified any developmental concerns from March 31, 2020 to March 31, 2022 (end of study) using any outpatient physician billing diagnostic code (required to accompany physician fee codes) for a developmental delay (gross motor, fine motor, speech and/or language) or hospital and emergency department records of a developmental delay (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510).13 The outpatient diagnostic codes used, while not validated against chart review, have face validity and are used in mental and behavioral health performance measurement across Ontario.14
Covariates
We included several covariates in the analysis. Child factors included sex, gestational age at birth, neighbourhood level material deprivation and income quintiles, and rural/urban residence. Maternal factors included age at delivery, active mental illness within the previous 2 years, maternal comorbidities during pregnancy that may affect child development (diabetes, hypertension, preeclampsia) (eTable 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510), immigrant or refugee status, and recency of immigration. Physician factors included specialty of the child's usual primary care provider (e.g., pediatrics vs family medicine; defined as the physician who provided the greatest number of days of visits for primary care-based fee codes from birth to 18 months) and modality of the 18-month well-baby visit (in-person vs virtual). For descriptive analysis only, we included the specialty of provider who performed the 18-month well-baby visit and who first identified a developmental concern.
Data Sources
We used several linked health administrative and demographic databases from ICES, an independent, nonprofit for research institute whose legal status under Ontario's health information privacy law allows it to collect and analyze health care and demographic data without consent for health system evaluation and improvement. Individual patient-level records are linked using unique encoded identifiers from the health card number of every insured Ontario resident.
We identified 18-month well-baby visits and developmental delays using physician billings from the Ontario Health Insurance Plan (OHIP) Physician Claims Database. We used the Canadian Institute for Health Information Discharge Abstract Database (CIHI-DAD), and the National Ambulatory Care Reporting System (NACRS) to identify healthy children for the cohort creation and birth mother health characteristics. We linked birth mothers and their newborns through in-hospital obstetric delivery records using the ICES MOMBABY dataset. We obtained sociodemographic characteristics from the Registered Person's Database. We linked the child's postal code to Canadian census data for neighbourhood level income and rural/urban residence and to the Ontario Marginalization Index (ON-Marg); for measures of material deprivation. Birth mother's immigration or refugee status was obtained from the Immigration, Refugees and Citizenship Canada's Permanent Resident Database. For birth mother's health characteristics, we used CIHI-DAD, NACRS, the OHIP Physician Claims database, Same Day Surgery Database, and the Ontario Mental Health Reporting System.
Statistical Analysis
Baseline characteristics for those who received a well-baby visit were described by visit type, using standardized differences (SDiff) to explore balance across exposure groups with important differences defined as a SDiff > 0.10.15 We calculated the number of events (identification of a developmental delay) and the number of children who were eligible to receive a developmental delay diagnosis at 6, 12, and 24 months following the date of the well-baby visit, by visit type. We enumerated each type of developmental delay among children who received an enhanced or routine visit at 6, 12, and 24 months following the well-baby visit. A cumulative incidence curve was created to display the detection month by exposure categories. We used a piecewise Cox proportional hazards model with time separated into “early time period” and “late time period”. Adjusted hazard ratios were calculated with 95% confidence intervals using the aforementioned child, maternal, and physician covariates to compare the time with the identification developmental delay by visit type (enhanced vs routine). A sensitivity analysis analyzed time to identification of developmental delays specifically within outpatient care, excluding diagnoses made during emergency department visits or hospitalizations. Statistical analyses were conducted using SAS Version 9.4 (SAS Institute, Cary, NC).
Ethics Approval
ICES is a prescribed entity under Ontario's Personal Health Information Protection Act (PHIPA). Section 45 of PHIPA authorizes ICES to collect personal health information, without consent, for the purpose of analysis or compiling statistical information with respect to the management of, evaluation or monitoring of the allocation of resources to or planning for all or part of the health system without research ethics board review. The use of the data in this project is authorized under section 45 and approved by ICES' Privacy and Legal Office. The Reporting of Observational Studies in Epidemiology (RECORD) guidelines were followed.
RESULTS
Baseline Characteristics
After exclusions (eFig. 1, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510), the analytic sample consisted of a total of 99,277 children who received an 18-month well-baby visit in Ontario, Canada, of which 84% (n = 83,554) were enhanced visits, and 16% (n = 15,723) were routine visits. Most baseline characteristics were balanced between the 2 exposure groups. However, compared with the routine well-baby visit group, those in the enhanced well-baby visit group were slightly older (18.6 vs 18.5 months; SDiff: 0.13); had a lower proportion of children in the most deprived group (16% vs 20%; SDiff: 0.11); had a higher proportion of patients who saw a pediatrician (26% vs 16%; SDiff: 0.26) as their usual provider of care; and similarly, a higher proportion of patients who saw a pediatrician (26% vs 15%; SDiff: 0.28) as the provider who performed the 18-month visit. (Table 1).
Table 1.
Baseline Child, Maternal, and Provider-Level Characteristics of Children Born in Ontario, Canada, Between October 31, 2018, and May 31, 2020, by Type (Enhanced vs Routine) of 18-Month Well-Baby Visit
| Variable | Enhanced 18-mo Visit | Routine 18-mo Visit | Standardized Differences |
| Total (N) | 83,554 | 15,723 | |
| Age child at receipt of well-baby visit (mo) | |||
| Mean (SD) | 18.6 (0.9) | 18.5 (1.1) | 0.13 |
| Median (IQR) | 18 (18–19) | 18 (18–19) | 0.18 |
| Neighborhood income quintile | |||
| 1 (low) | 13,553 (16) | 3080 (20) | 0.09 |
| 2 | 15,368 (18) | 3165 (20) | 0.04 |
| 3 | 18,171 (22) | 3459 (22) | 0.01 |
| 4 | 19,499 (23) | 3260 (21) | 0.06 |
| 5 (high) | 16,833 (20) | 2732 (17) | 0.07 |
| Missing data | 130 (0) | 27 (0) | 0.00 |
| Material deprivation quintile | |||
| 1 (least deprived) | 21,273 (26) | 3265 (21) | 0.11 |
| 2 | 18,783 (23) | 3223 (21) | 0.05 |
| 3 | 15,822 (19) | 3026 (19) | 0.01 |
| 4 | 14,001 (17) | 2975 (19) | 0.06 |
| 5 (most deprived) | 13,306 (16) | 3147 (20) | 0.11 |
| Missing data | 369 (0) | 87 (1) | 0.02 |
| Rurality | |||
| Urban | 75,973 (91) | 14,153 (90) | 0.03 |
| Rural | 7482 (9) | 1549 (10) | 0.03 |
| Missing data | 99 (0) | 21 (0) | 0.00 |
| Mother's age at index date | |||
| Mean (SD) | 33.1 (4.8) | 32.7 (5.1) | 0.08 |
| Median (IQR) | 33 (30–36) | 33 (30–36) | 0.07 |
| Parity | |||
| 0 | 39,644 (47) | 6737 (43) | 0.09 |
| 1 | 30,449 (36) | 5920 (38) | 0.03 |
| 2+ | 13,461 (16) | 3066 (20) | 0.09 |
| Gestational age of child at birth | |||
| 37 | 7442 (9) | 1457 (9) | 0.01 |
| 38 | 18,930 (23) | 3605 (23) | 0.01 |
| 39 | 28,186 (34) | 5271 (34) | 0.00 |
| 40 | 20,048 (24) | 3770 (24) | 0.00 |
| 41 | 8800 (11) | 1576 (10) | 0.02 |
| 42–45 | 148 (0) | 44 (0) | 0.02 |
| Maternal gestational diabetes mellitus | |||
| No | 73,828 (88) | 13,861 (88) | 0.01 |
| Yes | 9726 (12) | 1862 (12) | 0.01 |
| Maternal pre-existing diabetes | |||
| No | 82,118 (98) | 15,437 (98) | 0.01 |
| Yes | 1436 (2) | 286 (2) | 0.01 |
| Maternal hypertension | |||
| No | 81,922 (98) | 15,376 (98) | 0.02 |
| Yes | 1632 (2) | 347 (2) | 0.02 |
| Maternal pre-eclampsia | |||
| No | 83,407 (100) | 15,695 (100) | 0.00 |
| Yes | 147 (0) | 28 (0) | 0.00 |
| Maternal severe mental illness (previous 2 yrs) | |||
| No | 82,483 (99) | 15,454 (98) | 0.04 |
| Yes | 1071 (1) | 269 (2) | 0.04 |
| Mother's immigration status | |||
| Non-immigrant | 58,636 (70) | 10,802 (69) | 0.03 |
| Non-refugee immigrant | 21,434 (26) | 4085 (26) | 0.01 |
| Refugee immigrant | 3484 (4) | 836 (5) | 0.05 |
| Recency of mother's immigration | |||
| > 5 yrs | 15,768 (19) | 3013 (19) | 0.01 |
| ≤ 5 yrs | 9150 (11) | 1908 (12) | 0.04 |
| Nonimmigrant | 58,636 (70) | 10,802 (69) | 0.03 |
| Usual provider of care | |||
| Family physician | 61,691 (74) | 13,235 (84) | 0.26 |
| Pediatrician | 21,705 (26) | 2455 (16) | 0.26 |
| No primary care provider | 110 (0) | 27 (0) | 0.01 |
| Otherb | 48 (0) | 6 (0) | 0.01 |
| Provider specialty who performed the 18-mo well-baby visit | |||
| Family physician | 61,767 (74) | 13,392 (85) | 0.28 |
| Pediatrician | 21,787 (26) | 2326–2330 (15)a | 0.28 |
| Otherb | 0 (0) | 1–5 (0)a | 0.03 |
| Provider specialty who recorded a developmental delay | |||
| Family physician | 4390 (5) | 868 (6) | 0.01 |
| Pediatrician | 7665 (9) | 1140 (7) | 0.07 |
| No developmental delay | 71,250 (85) | 13,657 (87) | 0.05 |
| Otherb | 249 (0) | 58 (0) | 0.01 |
| Modality of 18-mo visit | |||
| In-person | 83,136 (100) | 15,628 (99) | 0.01 |
| Virtual | 418 (1) | 95 (1) | 0.01 |
All data are presented as a number (%) unless otherwise indicated.
Cell sizes less than 6 were suppressed to ensure no reidentification risk.
Other = primary care provider excluding general practitioners/family physicians and pediatricians.
IQR, interquartile range.
Identification of Developmental Delays
The cumulative incidence curve depicting the timing of developmental delay identification by exposure group is shown in Figure 1, and the number of children identified with a developmental delay of those eligible at <1 month, 1 to 6 months, 7 to 12 months, and 13 to 24 months are shown in eTable 3, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510. Children who received an enhanced visit had the largest proportion identified with developmental delay over both prespecified periods (0–6 months and >6 months) following the 18-month visit. The most frequent specific diagnostic code was “specified delays in development,” observed in 6138 children (50.1%) who received an enhanced visit and 1016 children (49.5%) who received a routine visit. The second most frequent diagnostic code was “behaviour disorders of childhood and adolescence,” a broad diagnostic code commonly used where developmental concerns exist such as with communication and social development), representing over 3 quarters of all specific diagnoses, which was observed in 3154 children who received an enhanced visit (25.8%) and 464 children (22.6%) who received a routine visit (eTable 4, Supplemental Digital Content 1, http://links.lww.com/JDBP/A510).
Figure 1.
Cumulative incidence curve depicting the time to the identification of developmental delays by visit type (enhanced and routine well-baby visits), partitioning time intervals to 0 to 6 months and greater than 6 months.
In the first 6 months following the well-baby visit, after adjusting for child, maternal, and provider factors, compared with those with routine visits, children with an enhanced visit were more likely to have developmental delays identified (adjusted hazard ratio 1.19 95% confidence interval [CI] 1.11‒1.28). In the later period (>6 months after the well-baby visit), the hazard ratio between the enhanced and routine visit groups was 1.01 (95% CI: 0.95–1.08), indicating no significant difference in the rate of developmental delay identification. Results of the sensitivity analysis restricting identification of developmental delays to outpatient physician visits (where nearly all diagnoses occurred) yielded results that were not meaningfully different from the main analysis (Table 2).
Table 2.
Cox Proportional Hazards Model With Unadjusted and Adjusted Hazard Ratios for the Time to Identification of Developmental Delay, Including a Sensitivity Analysis of the Time to the Identification of Outpatient Developmental Delay
| Enhanced vs Nonenhanced Well-Baby Visit Time Intervals | Unadjusted HR (95% CI) | Adjusted HR (95% CI) |
| Time to any developmental delay identification | ||
| 0–6 mo | 1.27 (1.19‒1.36) | 1.19 (1.11‒1.28) |
| Greater than 6 mo | 1.06 (1.00‒1.13) | 1.01 (0.95‒1.08) |
| Time to outpatient developmental delay identification (sensitivity analysis) | ||
| 0–6 mo | 1.27 (1.19‒1.36) | 1.19 (1.11‒1.28) |
| Greater than 6 mo | 1.06 (1.00‒1.13) | 1.01 (0.95‒1.08) |
The models were adjusted for child factors (age at index date, sex, material deprivation marginalization quintile, rurality, gestational age at birth), maternal factors (age, active mental illness within the past 2 years, comorbidities, refugee status, parity), specialty of the usual primary care provider, and modality of care (virtual/in-person).
CI, confidence interval; HR, hazard ratio.
DISCUSSION
In this population-based cohort study of healthy children, receipt of an enhanced 18-month well-baby visit was associated with slightly earlier identification of developmental delays compared to receipt of a routine 18-month visit, even after accounting for child, maternal, and provider factors. Differences in the rate of identification dissipate 6 months after the 18-month assessment. Findings suggest using enhanced developmental screening tools at this critical milestone may facilitate earlier recognition of developmental concerns and support early intervention. Although the differences observed were modest, their clinical importance is likely dependent on the timeliness and accessibility of early intervention services.
Currently, the Canadian Task Force on Preventive Health does not support screening for developmental delays in children who do not present with signs or symptoms due to insufficient evidence for the benefits and harms.7,11 The findings of this study add to the body of evidence in support of universal screening for children aged 18 months with benefits observed shortly after the screening though these benefits are not sustained beyond 6 months after the screen. Evidence previously reviewed by the Task Force suggests that screening increased the likelihood of a child receiving a referral for specialist or multidisciplinary evaluation,16 and eligibility for federally funded early intervention services but noted a scarcity of evidence for improved health outcomes.16 The Canadian Task Force's review found insufficient evidence to show screening for developmental delay in children aged 1 to 4 years with no known developmental concerns improved outcomes such as cognitive functions, academic performance, mental health, quality of life, survival, and functionality as an adult,7 but it did not include patient-reported outcomes, which are increasingly being recognized as quality indicators of patient care.17 Further research on the relationship of screening to such outcomes is warranted.
Reluctance to recommend universal developmental screening can be found globally in policies and practices across jurisdictions.10 In the United Kingdom, the National Screening Committee stated in 2005 that screening for developmental and behavioral problems is not recommended because of lack of sufficient evidence that screening would be beneficial to children.18 Other countries such as Australia and New Zealand follow up only on children whose caregivers have expressed concerns about their children's development.19 In such cases, the primary care provider refers the child for developmental screening.19 The findings of this study may have broader policy implications by contributing to the global evidence base on the value of early developmental screening, particularly in jurisdictions that are reconsidering or piloting universal screening programs.
Despite the lack of support for screening for developmental delays, there has been some movement to adopt it in practice in the United States and Canada. A population-based study of children in the United States indicates that there was a significant increase in developmental screenings among children aged 9 to 35 months between 2016 and 2020.20 In Ontario, 61% of children born in 2017 had an enhanced 18-month well-child visit, a significant increase since the inception of the incentive program in 2009.6 On the other hand, a study that analyzed 2019 American Academy of Pediatrics Periodic Survey data found that while the majority (98%) of pediatricians reported screening or surveillance for developmental delays, only 59% of them used standardized instruments to do so.21 Reported barriers to screening for developmental delays included difficulty prioritizing time for screening in office visits, inadequate reimbursement for conducting screening, and screening instruments not being available in electronic health records.21 While our group as previously demonstrated, and reaffirms here, that provider-level factors, including specialty type and practice model (e.g., pediatricians versus family physicians with and without patient enrollment models) are associated with the uptake of enhanced developmental screening,6 we have also identified that certain patient-level characteristics, such as indicators of poverty, may be important in uptake of developmental screening. As jurisdictions revisit or implement universal screening recommendations, funding models and reimbursement structures (such as Ontario's incentive program) may be key mechanisms to support uptake of developmental screening practices.
Findings from our study suggest that within 6 months following the well-baby visit, receipt of an enhanced visit was associated with a higher likelihood of having developmental delays identified. However, earlier identification in and of itself is insufficient; it can only be of real benefit if it is a steppingstone to accessible and effective intervention. Indeed, a major benefit of early detection that has been cited by many,22 and in the autism literature in particular, is the potential for early intervention and entry into socialized programs tailored to the child's needs.23 Studies show that early intervention may lead to significant improvements in language, cognitive, and social-emotional functioning in children with autism spectrum disorder and that they require less ongoing intervention during primary school.24 However, in many jurisdictions, timely access to early intervention services is not guaranteed. For example, in Ontario, which offers a publicly funded intensive behavioral intervention, the mean wait time is 2.7 years.25 Similarly, reports indicate that in the United States, wait times to see a specialist exceed 4 months, with one third of specialty care centers reporting wait times of more than a year.26 In some jurisdictions, reimbursement issues prevent families from receiving evaluations and early interventions altogether.26 Therefore, the benefit of an enhanced visit leading to detection in the 6-month period following a well-baby visit may be negated by issues of cost and accessibility of early intervention.
Limitations
There are important limitations to this study. As the study was conducted over the course of the pandemic, social distancing guidelines may have affected attendance at any well-baby visit, particularly for those with social vulnerability.27 Owing to data availability, we did not include children who may have attended visits in community health centers or with nurse practitioners.28 We did not include various physician-level factors (such as funding models and incentive programs), which have been shown to have important associations with the uptake of an enhanced well-baby visit as well as health outcomes.6 While we adjusted for the specialty of the provider of usual care and the provider who performed the well-baby visit, there may be residual confounders as specific clinics or physicians may have been more likely to perform enhanced screenings. In addition, we did not measure the effectiveness of screening tools such as the Nipissing District Developmental Screen, and prior research has cautioned using this measure on its own.29 We could not determine which specific standardized developmental screen each clinician used. Because the administrative data do not record name of the screening tool that is used, our analysis implicitly assumes that the screens employed were valid and comparable (when this may in fact not be the case). While an association was found between enhanced visits and earlier identification of developmental delay, this finding does not imply causation and there may be unmeasured confounding including from individual level income, health literacy, family education level, and likelihood of parental reporting. In addition, the distribution of the sample within the exposure groups (enhanced and nonenhanced) was not even, though findings represent a “real world” natural experiment at the whole province level. While the findings of this study are likely generalizable to other populations with access to primary care, study results are confined to Ontario's publicly funded health care system. Replicating the study in different health care structures and populations (such as private health care systems in the United States) would strengthen the generalizability of findings. Finally, diagnostic codes for developmental delay have not been validated though are widely used across the province for pediatric mental, neurodevelopmental, and behavioral health system monitoring.14
CONCLUSION
In this population-based study in a single payer publicly funded health system, we observed that children who received enhanced developmental screening at their 18-month well-baby visit had developmental concerns identified at a slightly earlier age compared with children who received routine developmental surveillance. Though modest, findings support the use of developmental screening in primary care to improve early detection of developmental concerns and referrals for intervention. For these benefits to be realized and made clinically important, there will need to be accessible and available early intervention for children identified with developmental delays. Furthermore, additional research is needed on clinical and patient-reported outcomes that may benefit from early detection of developmental concerns. In addition, research regarding barriers to developmental screening and potential models for remediation is needed in order for implementation of such policy changes to be effective. Comparative policy analyses across jurisdictions and associated impacts, including unintended consequences of policy changes, would also be enlightening.
Supplementary Material
Footnotes
This study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health (MOH) and the Ministry of Long-Term Care (MLTC). This study was also supported by the Canadian Institutes of Health Research (CIHR) Grant UIP-178845 awarded to N.R. Saunders, E. Cohen, and A. Guttmann. A. Guttmann is supported by a CIHR Canada Research Chair (2021-00104). The opinions, results and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by ICES or the Ontario MOH is intended or should be inferred. Parts of this material are based on data and/or information compiled and provided by CIHI and the Ontario Ministry of Health. The analyses, conclusions, opinions and statements expressed herein are solely those of the authors and do not reflect those of the funding or data sources; no endorsement is intended or should be inferred. Parts or whole of this material are based on data and/or information compiled and provided by Immigration, Refugees and Citizenship Canada (IRCC) current to September 30, 2020. However, the analyses, conclusions, opinions and statements expressed in the material are those of the author(s), and not necessarily those of IRCC. We thank the Toronto Community Health Profiles Partnership for providing access to the Ontario Marginalization Index. This document used data adapted from the Statistics Canada Postal CodeOM Conversion File, which is based on data licensed from Canada Post Corporation, and/or data adapted from the Ontario Ministry of Health Postal Code Conversion File, which contains data copied under license from Canada Post Corporation and Statistics Canada.
N.R. Saunders reported receiving personal fees from The BMJ Group, Archives of Disease in Childhood and an honorarium from the Canadian Post-COVID Condition Guideline Team, outside of the submitted work. E. Cohen reported being a member of the Committee to Evaluate Drugs, which provides advice to Ontario's Ministry of Health on public drug policy. The remaining authors declare no conflict of interest.
Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.jdbp.org).
E. Hamovitch and T. Raveendran contributed equally as co-first authors.
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Contributor Information
Emily Hamovitch, Email: emily.hamovitch@mail.utoronto.ca.
Tharani Raveendran, Email: tharani.raveendran@sickkids.ca.
Eyal Cohen, Email: eyal.cohen@sickkids.ca.
Azmina Altaf, Email: astrid.guttmann@ices.on.ca.
Christina Diong, Email: christina.diong@ices.on.ca.
Andrea Evans, Email: anevans@cheo.on.ca.
Therese A. Stukel, Email: therese.stukel@ices.on.ca.
Magdalena Janus, Email: janusm@mcmaster.ca.
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