Jens Dietrichson|Trine Filges|Julie Kaas Seerup|Rasmus H. Klokker|Bjørn C. A. Viinholt|Martin Bøg|Misja Eiberg
Targeted school?based interventions for improving reading and mathematics for students with or at risk of academic difficulties in Grades K?6: A systematic review
Danish Center for Social Science Research|Danish Center for Social Science Research|Danish Center for Social Science Research|Danish Center for Social Science Research|Danish Center for Social Science Research|Lundbeck (Denmark)|Danish Center for Social Science Research
low levels numeracy literacy skills associated range negative outcomes later life reduced earnings health obtaining information effective interventions children risk academic difficulties therefore importantthe main objective assess effectiveness interventions targeting students risk academic difficulties kindergarten grade 6we searched electronic databases 1980 july 2018 searched multiple international electronic databases total 15 seven national repositories performed search grey literature using governmental sites academic clearinghouses repositories reports working papers trial registries 10 sources hand searched recent volumes six journals contacted international experts lastly used included studies 23 previously published reviews citation trackingstudies meet following criteria included population population eligible review included students attending regular schools kindergarten grade 6 academic difficulties risk difficulties intervention included interventions sought improve academic skills conducted schools regular school year targeted selected indicated comparison included studies used interventioncontrol group design comparison group design included randomised controlled trials rct quasirandomised controlled trials qrct quasiexperimental studies qes outcomes included studies used standardised tests reading mathematics setting studies carried regular schools oecd country includeddescriptive numerical characteristics included studies coded members review team review author independently checked coding used extended version cochrane risk bias tool assess risk bias used randomeffects metaanalysis robustvariance estimation procedures synthesise effect sizes conducted separate metaanalyses tests performed within three months end interventions shortterm effects longer followup periods shortterm effects performed subgroup moderator analyses focused instructional methods content domains assessed sensitivity results effect size measurement outliers clustered assignment treatment risk bias missing moderator information control group progression publication biaswe found total 24414 potentially relevant records screened 4247 full text included 607 studies met inclusion criteria included 205 studies wide range intervention types least one metaanalysis 202 interventioncontrol studies 3 comparison designs reasons excluding studies analysis high risk bias 257 compared two alternative interventions 104 studies lacked necessary information 24 studies used overlapping samples 17 studies total number student observations analysed studies 226745 93 rcts among 327 interventions included metaanalysis interventioncontrol contrasts 86 united states target group consisted average 45 girls 65 minority students 69 lowincome students mean grade 24 studies included metaanalysis moderate high risk biasthe overall average effect sizes es shortterm followup outcomes positive statistically significant es 030 95 confidence interval ci 025 034 es 027 95 ci 017 036 respectively effect sizes correspond around one third one half achievement gap fourth grade students high low socioeconomic status united states 58 chance randomly selected score intervention group student greater score randomly selected control group studentall measures indicated substantial heterogeneity across shortterm effect sizes followup outcomes pertain almost exclusively studies examining smallgroup instruction adults effects reading measures followup effect sizes considerably less heterogeneous shortterm effect sizes although still statistically significant heterogeneitytwo instructional methods peerassisted instruction smallgroup instruction adults large statistically significant average effect sizes robust across specifications subgroup analysis shortterm effects es around 035045 metaregressions adjusted methods content domains study characteristics significantly larger effect sizes computerassisted instruction coaching personnel incentives progress monitoring peerassisted instruction also significantly larger effect sizes mediumgroup instruction besides peerassisted instruction smallgroup instruction methods consistently significant across analyses tried isolate association specific method effect sizes however analyses showed statistically significant heterogeneity also within categories instructional methodswe found little evidence effect sizes larger content domains others fractions significantly higher associations effect sizes math domains six studies interventions targeting fractions found evidence adverse effects sense method domain robustly negative associations effect sizesthe metaregressions revealed significant moderators interventions higher grades tend somewhat lower effect sizes whereas significant differences qes rcts general tests tests subdomains math tests reading testsour results indicate interventions targeting students risk academic difficulties kindergarten grade 6 average positive statistically significant shortterm followup effects standardised tests reading mathematics peerassisted instruction smallgroup instruction likely effective components interventionswe believe relatively large effect sizes together substantial unexplained heterogeneity imply schools reduce achievement gap students risk academic difficulties notatrisk students implementing targeted interventions research design effective interventions needed