School start time delays and high school educational outcomes: Evidence from the START/LEARN study

May combine two claims.

In an experimental study, sleep-deprived adolescents had lower test scores and poorer attention than those with healthy sleep.

“In a simulated school day with learning tasks and assessments, sleep-deprived adolescents had lower test scores and paid poorer attention (Beebe et al., 2010).”

• cites Beebe et al., 2010 sourceSupported

May combine two claims.

Sleep deprivation negatively affects attention, working memory, and learning.

“Sleep deprivation also negatively affects attention, working memory, and learning (Alhola and Polo-Kantola, 2007; Krause et al., 2017; Walker and Stickgold, 2006).”

• cites Alhola and Polo-Kantola, 2007 sourceSupported
• cites Krause et al., 2017 sourceSupported
• cites Walker and Stickgold, 2006 sourceNot checked — no full text of the source

May combine two claims.

Delaying high school start times is a promising policy intervention for improving adolescents' educational performance as well as sleep and health.

“Thus, delaying high school start times is a promising policy intervention that not only improves adolescents’ sleep, health, and behavior (Minges and Redeker, 2016) but can also strengthens their educational performance.”

• cites Minges and Redeker, 2016 sourceSupported

• AssumptionThe authors state this as an assumption: In the absence of the policy change, outcome trends would have been parallel between policy change and comparison schools, and the comparison group is a good proxy for the counterfactual change in the treated group.

May combine two claims.

Most US research on high school start time changes finds later start times associated with fewer late arrivals, fewer absences, and fewer disciplinary problems, though some studies show null or opposite findings.

“Though most research on high school start time changes in the United States finds that later school start times are associated with fewer late arrivals (Dunster et al., 2018; Lenard et al., 2020; Owens et al., 2010; Thacher and Onyper, 2016; Wahlstrom et al., 2014), fewer absences (Lenard et al., 2020; McKeever and Clark, 2017; Wahlstrom et al., 2014), and fewer disciplinary problems (Thacher and”

• cites Dunster et al., 2018 sourceSupported
• cites Lenard et al., 2020 sourceNot checked — no full text of the source
• cites Wahlstrom et al., 2014Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S3 (load-bearing).

Prior research indicated that school start times have a larger effect on absences, late arrivals, and grades in first period courses.

“Prior research has indicated that school start times have a larger effect on absences, late arrivals, and grades in first period courses (Bastian and Fuller, 2018; Dunster et al., 2018), though these studies used a less rigorous design than that presented here.”

• cites Bastian and Fuller, 2018 sourceNot checked — no full text of the source
• cites Dunster et al., 2018 sourcePartly supported

  The Results (page unavailable) report fewer first-period absences and late arrivals after the later start time at Franklin High School, but no change at Roosevelt High School. The paper does not show that these effects were larger in first period than in other periods. Its grade analysis used science classes drawn from several periods and does not establish a larger effect on first-period grades. (LLM, conf=0.87)

  Experimental — accuracy not yet measured

May combine two claims.

The analytic sample included 2,153 adolescents, of whom 51% were male, 20% non-white, 18% received FRPL, and 82% had a parent who graduated college.

“The analytic sample included 2,153 adolescents, of whom 51% were male, 20% were non-white, 18% received free-or-reduced-price lunch, and 82% had a parent who graduated college.”

May combine two claims.

Late arrivals increased over time for all students, but the increase was smaller in policy change schools than comparison schools.

“Late arrivals increase over time for all students, but this increase was more modest in policy change schools than comparison schools.”

May combine two claims.

Policy change and comparison schools differed at baseline in demographic composition: policy change schools had more non-white students and more students with a college-graduate parent.

“Students who attended policy change schools were 50% male, 25% non-white, 19% free-or-reduced-price lunch recipients, and 85% students with a college graduate parent. Students in comparison schools were 52% male, 13% non-white, 16% free-or-reduced price lunch recipients, and 77% students with a college-graduate parent.”

May combine two claims.

The start time delay did not have an immediate effect on absences at follow-up 1; both groups had about 9 absences per year.

“The start time delay did not have an immediate effect on absences, with students in both policy conditions having about 9 absences per year at follow-up 1.”

The quote only partly states this claim.

At follow-up 2, students in policy change schools had about three fewer late arrivals per year than comparison schools (p<0.001).

“A school start time delay of 50 to 65 minutes led to 3 fewer late arrivals, 1 fewer absence, a 14% lower probability of behavior referral, and 0.07-0.17 higher GPA in policy change schools versus comparison schools.”

May combine two claims.

GPA trajectories were parallel before baseline and through follow-ups 1a and 1b, then diverged at follow-ups 2a and 2b.

“For both measures, trajectories of GPA were parallel before baseline and through follow-ups 1a and 1b. These trajectories diverged at follow-ups 2a and 2b, however.”

The quote only partly states this claim.

At follow-up 2, the difference-in-differences estimate for behavior referral was 14 percentage points lower in policy change schools (p<0.001).

“A school start time delay of 50 to 65 minutes led to 3 fewer late arrivals, 1 fewer absence, a 14% lower probability of behavior referral, and 0.07-0.17 higher GPA in policy change schools versus comparison schools.”

May combine two claims.

Students who experienced a start time delay had less steeply declining GPA trajectories than comparison students, though GPA decreased over time in all schools.

“Students who experienced a school start time delay had less steeply declining GPA trajectories than students who did not experience a school start time delay, though GPA decreased over time in all schools.”

May combine two claims.

The estimated effects were larger at the second follow-up than the first, and for absences and GPA the differences appeared only at the second follow-up.

“Effects were larger in the second year of follow-up than in the first year of follow-up, and differences in absences and GPA emerged in the second year of follow-up only.”

May combine two claims.

Most associations were similar across demographic groups, and there was no moderation of effects on absences or by race.

“Most associations were similar across most groups, and we did not identify any moderation of effects on absences or by race.”

May combine two claims.

At baseline, comparison school students had a higher probability of behavior referral than policy change students (about 17% vs 3-5%), likely reflecting differences in schools' disciplinary practices.

“Students in comparison schools that did not experience a start time delay had a higher probability of experiencing a behavior referral than students in policy changes schools both before and after the school start time policy change, likely reflecting differences in schools’ disciplinary practices (Table 2 and bottom panel of Figure 1).”

May combine two claims.

The 50-65 minute start time delay in this study extended students' objectively measured nightly sleep by about 40 minutes per school night, sustained at both follow-ups.

“This policy change extended students’ objectively-measured nightly sleep, measured using wrist actigraphy, by 40 minutes per night on school nights at follow-ups that occurred both one and two years later (Widome et al., 2020a).”

• cites Widome et al., 2020aNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

School start time delays increased high school graduation rates.

“one study has found that school start time delays increased high school graduation rates (McKeever and Clark, 2017).”

• cites McKeever and Clark, 2017 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

Moderation of behavior referral effects could not be tested because of small sample sizes.

“(We were not able to test moderation for behavior referrals due to small sample sizes.)”

Classified as probably not a substantial claim. May combine two claims.

The analytic models included school and student random effects and adjusted for sex, ethnoracial group, FRPL, and parental college completion.

“Our models included both school and student random effects (u0j is a random intercept for school) and adjusted for students’ sex, ethnoracial group, free or reduced-price lunch receipt, and parental college completion.”

Probably not a substantial claim: may not pass S3 (load-bearing).

It was not feasible to adjust for race in models of behavior referrals due to extremely small cell sizes.

“(Due to extremely small cell sizes, it was not feasible to adjust for race in models of behavior referrals.)”

May combine two claims.

The study had only one pre-treatment data point (grade 9), so additional pre-treatment data would have strengthened the parallel trends assumption.

“Additional pre-treatment data would have strengthened the parallel trends assumption, as we have only one pre-treatment data point (grade 9).”

• AssumptionThe authors state this as an assumption: In the absence of the policy change, outcome trends would have been parallel between policy change and comparison schools, and the comparison group is a good proxy for the counterfactual change in the treated group.

Probably not a substantial claim: may not pass S3 (load-bearing).

Educational outcome data came from school district administrative records.

“All data on educational outcomes were provided by school districts and were drawn from administrative records.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

A high school start time delay improved reading scores for girls only but did not change math scores.

“Groen and Pabilonia (2019) found that a high school start time delay improved reading scores (for girls only) but did not change math scores.”

• cites Groen and Pabilonia, 2019 sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

It is unclear whether the effect of a start time delay on educational outcomes would be similar for less advantaged students or schools.

“This is a relatively advantaged sample of students and schools, and it is not clear whether the effect of a school start time delay on educational outcomes would be similar for students or schools with fewer resources.”

Classified as probably not a substantial claim.

Covariates were included to account for factors that might have influenced both district decisions to delay start times and students' educational outcomes.

“We included these covariates to attempt to account for factors that may have contributed to both which school districts chose to delay their start times and the educational outcomes of students in these districts.”

Classified as probably not a substantial claim.

The analyses included 2,153 adolescents (87% of participants) for whom policy condition, school, educational outcomes, and demographic covariates could be determined.

“Of the 2,466 adolescents who participated in START/LEARN, our analyses include 2,153 adolescents (87% of participants) for whom we could determine each student’s policy condition, specific school, educational outcomes, and demographic covariates.”

Classified as probably not a substantial claim. May combine two claims.

Comparing grades across schools is complicated because course grades for the same performance vary between schools, and differing GPA weighting schemes may exacerbate this.

“Third, comparing student grades across schools is complex because course grades for the same level of performance vary between schools. In our study, these differences may be exacerbated by differing GPA weighting schemes.”

May combine two claims.

With a causally rigorous approach, GPA is affected by school start time, but only two years after a policy change.

“With our causally rigorous approach, we find that GPA is affected by school start time, but only two years after a policy change.”

• AssumptionThe authors state this as an assumption: In the absence of the policy change, outcome trends would have been parallel between policy change and comparison schools, and the comparison group is a good proxy for the counterfactual change in the treated group.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The START/LEARN study was approved by the University of Minnesota IRB and participating school districts' research review panels.

“The START/LEARN study was approved by the University of Minnesota Institutional Review Board and participating school districts’ research review panels.”

May combine two claims.

The study is a natural experiment; schools and districts were not randomly assigned to policy conditions, so confounding by other student or school characteristics is possible.

“First, this is a natural experiment. Schools/districts were not randomly assigned to policy conditions by the research team, meaning that there could be confounding by other student or school characteristics.”

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

Policy changes that improve educational outcomes can promote health equity by addressing a fundamental cause of health disparities.

“Additionally, policy changes that improve educational outcomes can promote health equity by addressing a fundamental cause of health disparities (Link and Phelan, 1995).”

• cites Link and Phelan, 1995Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.