Coaching dosage shows precisely estimated null effects: more coaching hours are not associated with larger program effects¶

Claim · All claims
Evidence · 1 study · quant-synthesis r? · q2
Currency · newest study 2018 · checked against its sources 2026-10-19 (automated, 1 of 1 entry) · not reviewed by a person

Subclaims¶

q2 i? For both total coaching hours and total PD hours, the meta-analytic regressions find no evidence that higher dosage produces larger effects on instruction or achievement. → Kraft 2018

Evidence¶

Kraft 2018¶

Kraft, M.A., Blazar, D., Hogan, D. (2018). The effect of teacher coaching on instruction and achievement: A meta-analysis of the causal evidence. Review of Educational Research, 88(4), 547-588. https://doi.org/10.3102/0034654318759268

q2 · i? · quant-synthesis · r?

Exploratory meta-analytic regressions across the 60 studies; the authors call the dosage measure exploratory due to inconsistent reporting of hours across studies. No effect size is printed for this null finding.

"for both measures of dosage – total hours of coaching, and total hours of PD when coaching is paired with other program features – we fail to find any evidence in support of the hypothesis that coaching must be high-dosage to be effective. We find very precisely estimate null effects for both instruction and achievement outcomes."

Studies bearing on this claim¶

Does more coaching time, or more frequent contact, go with larger effects? This table gathers the studies behind this claim and the 3 narrower claims that bear on it: 4 distinct studies (2 qualitative, 1 quant-synthesis, 1 associational), q2, 0 of 4 with an effect size coded. One row per study, codes as each entry records them; no effect is averaged and no verdict is drawn. Built by scripts/synthesize_claim.py from eval/synthesis/; a row that looks wrong is fixed on the claim it comes from.

Discussion¶

Related Claims¶

- Pairing coaching with group trainings is associated with larger effects on instruction and achievement; instructional materials with larger, and video libraries with smaller, effects on instruction — the general claim this finding bears on, with the studies behind it¶

• The authors judge insufficient instructional intensity (dosage) as the primary factor behind the null result of learning strategies instruction in adult education — related
• Frequency of coaching field support varies across California induction programs and is positively related to administrators' ratings of program effectiveness — reports the opposite
• No specific coaching dosage is established as necessary; coaching outcomes appear more sensitive to coaching quality than dosage, with sustained duration favoring comprehensive coaching — possibly the same claim (merge candidate)
• Time spent between teachers and coaches is one of the most important factors in a successful coaching program — reports the opposite
• Multi-session game interventions show significantly larger learning benefits than single-session interventions, while total play duration shows no association with effect size — related