There were some errors in the original published article [1]. Firstly relating to the calculation of the confidence intervals for four of the studies included in the meta-analysis, [2, 3, 4, 5] which are detailed below. Secondly one of the papers, Whybrow et al. was incorrectly cited as being published in 2007, when it was published in 2006 [2]

Eyles, H

Mytton, Oliver

Ni Mhurchu, C

Nnoaham, K

Scarborough, P

BMC Public Health

O. T. Mytton

K. Nnoaham

H. Eyles

P. Scarborough

C. Ni Mhurchu

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Erratum to: systematic review and meta-analysis of the effect of increased vegetable and fruit consumption on body weight and energy intake

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Mytton, OT

Apollo (Cambridge)

ERRATUM Open AccessErratum to: systematic review and meta-analysis of the effect of increasedvegetable and fruit consumption on bodyweight and energy intakeO. T. Mytton*, K. Nnoaham, H. Eyles, P. Scarborough and C. Ni MhurchuErratumThere were some errors in the original published article[1]. Firstly relating to the calculation of the confidenceintervals for four of the studies included in the meta-analysis, [2–5] which are detailed below. Secondly one ofthe papers, Whybrow et al. was incorrectly cited as beingpublished in 2007, when it was published in 2006 [2].Description of errors relating to derivation of 95%confidence intervalsThe study by Whybrow et al. had three arms (control,arm A, arm B) [2]. We had effectively included the con-trol arm twice by using it as the control for both arm Aand arm B of the study. We have now halved the size ofthe control group (allocating eight participants in onecontrol group and nine to the second control group),which is one approach to correct for the potential problemof double counting the control group [6].We used an incorrect approach to derive standard errorsfor the difference in change between two arms of thestudy, from the standard errors for change in each arm ofthe study. This affected three studies [2, 5, 7]. We havenow corrected this.Third there was a transcription error made whenextracting data from the paper by Christensen et al. [4].The correct p-value for the difference in change in bodyweight between the control and intervention arm is 0.18.Additional files 1 and 2: Tables S1 and S2 below showthe derivation of the standard error for the difference inchange in body weight between the control and inter-vention group, deriving standard errors from p-valuesand from standard errors for the change in body weightwithin each group respectively.Effect of these errors on resultsThe error in derivation of standard errors effects Figs.2a and 3a in the original manuscript. Revised copies ofthese figures are shown below.The first line of the Results, under Primary Analysis,should read: “The mean change in body weight was0.54 kg (95% CI: -1.05 to −0.04; n = 8; I2 for hetero-geneity = 73%, p < 0.01) less in the ‘high vegetable andfruit’ intake arms than in the ‘low vegetable and fruitintake’ arms (Fig. 2a).”The equivalent line in the Results section of the Ab-stract should read: “The mean change in body weight was-0.54kg (95% CI: -1.05 to -0.04; n=8; I2 for heterogeneity= 73%, p<0.01) less in the ‘high vegetable and fruit’ intakearms than in the ‘low vegetable and fruit intake’ arms.”The first paragraph of the Sensitivity Analysis shouldbe amended to read: “Undertaking a one study removedanalysis did not change the direction of the finding withrespect to body weight. The point estimates of effect sizefor body weight ranged from -0.32 kg to -0.74 kg com-paring ‘high vegetable and fruit intake’ to ‘low vegetableand fruit intake’. The difference only remained signifi-cant when two of the seven studies, Petersen et al andSmith-Warner et al, were removed. After removal ofWeerts et al, the effect estimate was -0.32 kg (95% CI:-0.71 to 0.06; n=7; I2 for heterogeneity = 56%, p=0.04).”The second sentence of the Secondary Analysis sectionshould read as follows: “Change in body weight for typea studies (-0.86 kg, 95% CI: -1.65 to -0.07) was greaterthan for type b studies (-0.25, 95% CI: -1.08 to 0.58),although the differences were not significant on meta-regression (p = 0.19) and largely disappeared afterelimination of the Weerts et al. study (-0.38 for type astudies vs -0.25 for type b studies).” The last sentenceof this section should read: “We could not find strong* Correspondence: otm21@medschl.cam.ac.ukCentre for Diet and Activity Research, MRC Epidemiology Unit, University ofCambridge, Cambridge, UK© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Mytton et al. BMC Public Health  (2017) 17:662 DOI 10.1186/s12889-017-4664-2evidence of a dose–response relationship between thedifference in vegetable & fruit intake and change inbody weight, on meta-regression (gradient = -0.150 kgper 100 g vegetable and fruit, p = 0.32).”The third sentence of the second paragraph under thesection entitled “Comparison with other studies”, in theDiscussion should read: “Excluding the outlier our pointestimates are comparable (-0.32 kg vs -0.16 kg) withoverlapping confidence intervals.”Effect of these errors on conclusionsIn summary the use of the amended standard errorshas had two principle effects. First our estimate ofthe primary effect size is more conservative (−0.54 kgvs −0.68 kg), due to re-weighting of the studies. Al-though the observed decrease is still statistically sig-nificantly. Second when we remove the outlier thedifference is no longer significantly different to zero.NOTE: Weights are from random effects analysisOverall  (I-squared = 73.0%, p = 0.001)Weerts 2009Whybrow 2006 (300g)Dow 2012Basu 2010Whybrow 2006 (600g)IDChristensen 2013Peterson 2011Smith-Warner 2000Study-0.54 (-1.05, -0.04)-4.41 (-6.77, -2.06)-0.77 (-1.63, 0.09)-0.50 (-1.30, 0.30)-0.90 (-1.88, 0.08)-0.62 (-1.46, 0.22)ES (95% CI)-0.90 (-2.20, 0.40)0.40 (-0.05, 0.85)-0.09 (-0.40, 0.22)100.003.7712.8213.5511.5713.04Weight8.7017.6118.94%weight loss (kg)  weight gain (kg) 0-6.77 6.77Fig. 2 Revised figure 2 a Meta-analyses of the effect of high vegetable and fruit intake compared to low vegetable and fruit intake on bodyweight (Amended)0.511.5-4 -2 0 2Difference in body weight (kg)Funnel plot with pseudo 95% confidence limitsFig. 3 a Funnel plots for the outcomes of change in body weight (Amended)Mytton et al. BMC Public Health  (2017) 17:662 Page 2 of 3Removing other studies (individually) also results in anon-significant result.While the revised results may provide weaker evidenceto support an assertion that increases in fruit and vege-table consumption may result in loss of body weight, wethink the overall effect of these statistical errors on ourresults and conclusions is slight.In our manuscript, our conclusion was intentionallyworded cautiously, reflecting greater uncertainty thanwas captured in the published confidence intervals (e.g.due study quality and study design). Our original con-clusion was that “Promoting increased fruit and vege-table consumption, in the absence of specific advice todecrease consumption of other foods, appears unlikelyto lead to weight gain in the short-term and may have arole in weight maintenance or loss.”We do not feel the amended results alter these conclu-sions. Whilst some of the results could (e.g. the estimateafter removal of the Weert’s et al. study) be consistentwith a gain in body weight, the amended results appearmost consistent with an increase in fruit and vegetableconsumption having either no effect on body weight, ora small reduction.Additional filesAdditional file 1: Table S1. Derivation of standard errors for thedifference in change in body weight between control and interventionfrom p-values (necessary for four studies included in the review). T-scoreand standard errors were imputed in Microsoft Excel, following theprocess outlined in the Cochrane Handbook (section 7.7.3.3) [8].(DOCX 12 kb)Additional file 2: Table S2. Derivation of standard errors for thedifference in change in body weight between control and interventionfrom standard errors for each group (necessary for three studies).*size of control group halved; and estimate of SE correspondinglyadjusted (values used in calculations are shown in the table); thefollowing formula used to calculate the standard errors for thedifference in change in body weight between control andintervention was: SE int−con ¼ﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃvarintnintþ varconnconq… (DOCX 12 kb)Received: 1 August 2017 Accepted: 2 August 2017References1. Mytton OT, Nnoaham K, Eyles H, Scarborough P, Ni Mhurchu C. Systematicreview and meta-analysis of the effect of increased vegetable and fruitconsumption on body weight and energy intake. BMC Public Health.2014;14:886.2. Whybrow S, Harrison CLS, Mayer C, Stubbs RJ. Effects of added fruits andvegetables on dietary intakes and body weight in Scottish adults. Br J Nutr.2006;95:496.3. Basu A, Du M, Leyva MJ, Sanchez K, Betts NM, Wu M, Aston CE, Lyons TJ.Blueberries decrease cardiovascular risk factors in obese men and womenwith metabolic syndrome. J Nutr. 2010;140:1582–7.4. Christensen AS, Viggers L, Hasselström K, Gregersen S. Effect of fruitrestriction on glycemic control in patients with type 2 diabetes–arandomized trial. Nutr J. 2013;12:29.5. Dow CA, Going SB, Chow H-HS, Patil BS, Thomson CA. The effects of dailyconsumption of grapefruit on body weight, lipids, and blood pressure inhealthy, overweight adults. Metabolism. 2012;61:1026–35.6. Higgins JPT, Green S. How to include multiple groups from one study.In: Cochrane handbook for systematic reviews of interventions v 5.1.0;2011. p. 16.5.4.7. Basu S, Seligman H, Winkleby M. A metabolic-epidemiologicalmicrosimulation model to estimate the changes in energy intake andphysical activity necessary to meet the healthy people 2020 obesityobjective. Am J Public Health. 2014;104:1209–16.8. Green S, Higgins J: Cochrane handbook for systematic reviews ofinterventions. 2011.Mytton et al. BMC Public Health  (2017) 17:662 Page 3 of 3

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