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Zhu Y, Wang S, Qian Y, Hu J, Zhou H, Korivi M, Ye W, Zhu R. The Impact of Birth Season and Sex on Motor Skills in 2-Year-Old Children: A Study in Jinhua, Eastern China. Life (Basel) 2024; 14:836. [PMID: 39063590 PMCID: PMC11278476 DOI: 10.3390/life14070836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/26/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND This study investigates the effects of birth season and sex on the development of gross and fine motor skills in 2-year-old children in Jinhua, Eastern China. METHODS Conducted in Jinhua, a city in central Zhejiang Province, Eastern China, this research involved 225 children, assessing their gross and fine motor skills using the Peabody Developmental Motor Scales, Second Edition. Scores were adjusted for age in months to avoid the relative age effect. Statistical analyses included MANOVA to evaluate the impacts of season and sex. RESULTS Sex had no significant impact on overall motor development scores (p > 0.05). However, the season of birth significantly affected fine motor quotient (FMQ) and total motor quotient (TMQ) (p < 0.05). Boys' motor skills were generally unaffected by season, whereas girls born in winter exhibited superior fine motor skills compared to those born in summer. CONCLUSIONS Seasonal environmental factors significantly influence early motor development, particularly fine motor skills in girls. These findings highlight the importance of considering seasonal variations in early childhood interventions aimed at enhancing exercise physiology and sports performance.
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Affiliation(s)
- Yuanye Zhu
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Shuying Wang
- College of Physical Education, North University of China, Taiyuan 030051, China;
| | - Yongdong Qian
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Jiahui Hu
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Huiling Zhou
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Mallikarjuna Korivi
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Weibing Ye
- Institute of Human Movement and Sports Engineering, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua 321004, China; (Y.Z.); (Y.Q.); (J.H.); (H.Z.); (M.K.)
| | - Rong Zhu
- Department of Sports Science, Wenzhou Medical University, Wenzhou 325035, China
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Weiler HA, Hazell TJ, Majnemer A, Vanstone CA, Gallo S, Rodd CJ. Vitamin D supplementation and gross motor development: A 3-year follow-up of a randomized trial. Early Hum Dev 2022; 171:105615. [PMID: 35777122 DOI: 10.1016/j.earlhumdev.2022.105615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 06/16/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND Vitamin D status during pregnancy, early childhood and season-at-birth are implicated in gross motor development (GMD). AIM To test whether vitamin D intake in infancy and season-at-birth affect GMD in early childhood. STUDY DESIGN 3-year follow up study of a single-center trial. SUBJECTS Healthy infants (n = 116) were allocated to 400 (standard-of-care), 800 or 1200 IU/day of vitamin D3 supplementation from 1 to 12 months; n = 70 returned for follow-up at 3-years. OUTCOME MEASURES The main outcome was GMD using the Peabody Developmental Motor Scales-2 which includes gross motor quotient (GMQ) and stationary, locomotion and object manipulation subtests. RESULTS GMQ scores were normal (≥85) in 94 %. An interaction between dosage group and season-at-birth (p = 0.01) was observed for GMQ and stationary standardized score; among winter/spring born children, the 1200 IU/d scored higher vs. 400 and 800 IU/d groups. Object manipulation standardized score was higher (p = 0.04) in children in the 1200 vs. 400 IU/d group, without interaction with season-at-birth. CONCLUSIONS GMD in young children who received 400 IU/d of supplemental vitamin D in infancy is not influenced by season-at-birth. This dose of vitamin D of 400 IU/d as recommended in North America adequately supports GMD. The modest enhancement in GMD with 1200 IU/d in winter/spring born children requires further study.
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Affiliation(s)
- Hope A Weiler
- School of Human Nutrition, McGill University, Ste Anne de Bellevue, QC, Canada; Nutrition Research Division, Bureau of Nutritional Sciences, Health Products and Food Branch, Health Canada, Ottawa, ON, Canada.
| | - Tom J Hazell
- School of Human Nutrition, McGill University, Ste Anne de Bellevue, QC, Canada; Department of Kinesiology and Physical Education, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Annette Majnemer
- School of Physical and Occupational Therapy, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | | | - Sina Gallo
- School of Human Nutrition, McGill University, Ste Anne de Bellevue, QC, Canada; Nutritional Sciences, University of Georgia, Athens, GA, United States of America
| | - Celia J Rodd
- School of Human Nutrition, McGill University, Ste Anne de Bellevue, QC, Canada; Department of Pediatrics, Faculty of Medicine, McGill University, Montreal, QC, Canada; Department of Pediatrics and Child Health, Children's Hospital Research Institute, University of Manitoba, Winnipeg, MB, Canada
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Matsubara K, Hattori T, Narumi S. Achievement of Developmental Milestones Recorded in Real Time: A Mobile App-Based Study. J Pediatr 2022; 245:201-207.e9. [PMID: 35182581 DOI: 10.1016/j.jpeds.2022.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 01/24/2022] [Accepted: 02/11/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To clarify the characteristics of milestone achievement of Japanese infants using data assessed and recorded in real time via a Web-based app by caregivers. STUDY DESIGN Between 2014 and 2019, the achievement of developmental milestones of 16 627 Japanese infants were recorded via the mobile app Papatto Ikuji along with pertinent information including sex, birth date, anthropometric measurements, and information on feeding. The milestones consisted of 20 items belonging to 4 domains: personal-social, fine motor-adaptative, language, and gross motor. The distribution of age at milestone achievement was compared with 4 conventional normative data. Subgroup analyses according to sex, season of birth, and feeding methods were performed with restricted mean survival time analysis. RESULTS Age distributions of milestone achievement were generally similar in the app-based and conventional data. The exception was "Smile responsively," for which the age at achievement seemed higher in the app-based data. Subgroup analyses showed female-dominant sex differences in the achievement of person-social and language milestones. The results also showed seasonality in achievement of gross motor milestones, with earlier achievement in infants born in winter compared with those born in summer. CONCLUSIONS We describe mobile app-based data on developmental milestone achievements that were recorded in real time. The app-based data were generally comparable with conventional normative data, suggesting that its potential to assess the development of children in real time. This could be used complementarily with the current well-child visits at scheduled time points.
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Affiliation(s)
- Keiko Matsubara
- Department of Molecular Endocrinology, National Center for Child Health and Development, Tokyo, Japan.
| | | | - Satoshi Narumi
- Department of Molecular Endocrinology, National Center for Child Health and Development, Tokyo, Japan
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Boonzaaijer M, Suir I, Mollema J, Nuysink J, Volman M, Jongmans M. Factors associated with gross motor development from birth to independent walking: A systematic review of longitudinal research. Child Care Health Dev 2021; 47:525-561. [PMID: 33210319 PMCID: PMC8252538 DOI: 10.1111/cch.12830] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 01/31/2023]
Abstract
AIM The aim of this study is to gain more insight into child and environmental factors that influence gross motor development (GMD) of healthy infants from birth until reaching the milestone of independent walking, based on longitudinal research. BACKGROUND A systematic search was conducted using Scopus, PsycINFO, MEDLINE and CINAHL to identify studies from inception to February 2020. Studies that investigated the association between child or environmental factors and infant GMD using longitudinal measurements of infant GMD were eligible. Two independent reviewers extracted key information and assessed risk of bias of the selected studies, using the Quality in Prognostic Studies tool (QUIPS). Strength of evidence (strong, moderate, limited, conflicting and no evidence) for the factors identified was described according to a previously established classification. RESULTS In 36 studies, six children and 11 environmental factors were identified. Five studies were categorized as having low risk of bias. Strong evidence was found for the association between birthweight and GMD in healthy full-term and preterm infants. Moderate evidence was found for associations between gestational age and GMD, and sleeping position and GMD. There was conflicting evidence for associations between twinning and GMD, and breastfeeding and GMD. No evidence was found for an association between maternal postpartum depression and GMD. Evidence for the association of other factors with GMD was classified as 'limited' because each of these factors was examined in only one longitudinal study. CONCLUSION Infant GMD appears associated with two child factors (birthweight and gestational age) and one environmental factor (sleeping position). For the other factors identified in this review, insufficient evidence for an association with GMD was found. For those factors that were examined in only one longitudinal study, and are therefore classified as having limited evidence, more research would be needed to reach a conclusion.
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Affiliation(s)
- Marike Boonzaaijer
- Research Group Lifestyle and Health, Institute of Human Movement StudiesHU University of Applied SciencesUtrechtThe Netherlands
| | - Imke Suir
- Research Group Lifestyle and Health, Institute of Human Movement StudiesHU University of Applied SciencesUtrechtThe Netherlands
| | - Jurgen Mollema
- Research Group Lifestyle and Health, Institute of Human Movement StudiesHU University of Applied SciencesUtrechtThe Netherlands
| | - Jacqueline Nuysink
- Research Group Lifestyle and Health, Institute of Human Movement StudiesHU University of Applied SciencesUtrechtThe Netherlands
| | - Michiel Volman
- Faculty of Social and Behavioural Sciences, Department of Pedagogical and Educational SciencesUtrecht UniversityUtrecht3584 CSThe Netherlands
| | - Marian Jongmans
- Faculty of Social and Behavioural Sciences, Department of Pedagogical and Educational SciencesUtrecht UniversityUtrecht3584 CSThe Netherlands
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Yasumitsu-Lovell K, Thompson L, Fernell E, Eitoku M, Suganuma N, Gillberg C. Birth month and infant gross motor development: Results from the Japan Environment and Children's Study (JECS). PLoS One 2021; 16:e0251581. [PMID: 34014944 PMCID: PMC8136702 DOI: 10.1371/journal.pone.0251581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/29/2021] [Indexed: 11/24/2022] Open
Abstract
The association between birth month and neurodevelopmental or psychiatric disorders has been investigated in a number of previous studies; however, the results have been inconsistent. This study investigated the association between birth month and child gross motor development at 6 and 12 months of age in a large cohort of infants (n = 72,203) participating in the Japan Environment and Children’s Study (JECS). Gross motor development was assessed using the Ages and Stages Questionnaire (ASQ-3). At 6 months and 12 months, 20.7% and 14.2%, respectively, had ASQ-3 indications of gross motor problems. Birth month was strongly associated with gross motor development at both time points, particularly at 6 months. Summer-born infants had the worst outcomes at both 6 months and 12 months of age. This outcome applied to the ASQ-3 score itself and to the adjusted Relative Risk (aRR), with the highest aRRs (relative to January-born) among August-born (aRR 2.51; 95%CI 2.27–2.78 at 6 months), and June-born (aRR 1.84; 95%CI 1.63–2.09 at 12 months). Boys had better scores than girls both at 6 and 12 months of age. We speculate that seasonal factors—such as maternal vitamin D deficiency and influenza infection—affecting the fetus in early pregnancy might account for the findings.
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Affiliation(s)
- Kahoko Yasumitsu-Lovell
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Environmental Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan
| | - Lucy Thompson
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Health and Wellbeing, University of Glasgow, Glasgow, Scotland
| | - Elisabeth Fernell
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Masamitsu Eitoku
- Department of Environmental Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan
| | - Narufumi Suganuma
- Department of Environmental Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan
- * E-mail:
| | - Christopher Gillberg
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Health and Wellbeing, University of Glasgow, Glasgow, Scotland
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Hermes L, Martins FK, Righi NC, Böck THO, Trevisan CM, Weinmann ARM, Valentini NC. Sazonalidade e fatores de risco associados ao desenvolvimento motor de lactentes nascidos a termo. CADERNOS BRASILEIROS DE TERAPIA OCUPACIONAL 2021. [DOI: 10.1590/2526-8910.ctoao2126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Resumo Introdução Diferentes fatores afetam o desenvolvimento motor no primeiro ano de vida, tendo sido pouco estudada a interferência da variação sazonal. Objetivo Investigar a influência da sazonalidade e de fatores de risco e proteção para o desenvolvimento motor de lactentes nascidos a termo, aos 7 e 10 meses de idade. Método Foram incluídos no estudo lactentes a termo (N=174) que vivenciaram os marcos de desenvolvimento referentes ao 2º e 3º trimestres no período de verão ou de inverno. Prontuários, entrevistas, e a Alberta Infant Motor Scale foram utilizados. Resultados A aquisição do sentar-se e engatinhar foi mais tardia nos grupos pós-inverno (p < 0,001). Quanto aos grupos de risco e sem risco para o desenvolvimento motor, observou-se, aos 7 meses, menor prevalência de planejamento da gravidez (p=0,015), menor tempo de aleitamento materno exclusivo (p=0,004) e de amamentação (p=0,012) no grupo com risco. Aos 10 meses, os lactentes do grupo de risco se caracterizaram pela menor idade gestacional (p=0,040), por serem filhos de mães mais velhas (p=0,020), maior número de irmãos (p=0,002), níveis mais elevados de pobreza (p=0,002) e maiores restrições de movimento (p=0,000). A regressão logística evidenciou que, aos 7 meses, o aleitamento materno foi a variável associada ao desenvolvimento motor, enquanto aos 10 meses, o número de filhos, a pobreza e a restrição de movimento do lactente explicaram a variação no desenvolvimento motor. Conclusão O clima frio não se mostrou um determinante isolado para o risco de atraso motor, variáveis ambientais foram mais influentes no modelo.
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Bai Y, Shang G, Wang L, Sun Y, Osborn A, Rozelle S. The relationship between birth season and early childhood development: Evidence from northwest rural China. PLoS One 2018; 13:e0205281. [PMID: 30307998 PMCID: PMC6181351 DOI: 10.1371/journal.pone.0205281] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 09/21/2018] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE To examine the correlation between birth season and early childhood development. BACKGROUND Almost all previous studies that examine the effect of birth season on early childhood development were conducted in developed countries with a limited sample size. The present study was conducted in poor, rural areas of western China, a developing region with a continental monsoon climate. METHOD We administered a hemoglobin test to 650 infants (52% boys), aged 8-10 months, using a Hemocue Hb 201+ finger prick system, and assessed the cognitive and psychomotor development of sample infants using Bayley Scales of Infant Development. RESULTS Infants born in winter have higher Hb concentrations (t = 3.63, p < 0.001) compared to infants born in summer. Similarly, cognitive development scores (t = 5.17, p < 0.001) and psychomotor development scores (t = 10.60, p < 0.001) were significantly higher among winter-born infants. CONCLUSION The findings point to the involvement of birth season in early childhood development and suggest that aspects of the environment shape the experiences that contribute to early childhood development. Policy suggestions such as providing infants with ample opportunities for movement and stimulation during the cold season are discussed.
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Affiliation(s)
- Yu Bai
- Centre for Experimental Economics in Education (CEEE), Shaanxi Normal University, Xi’an, Shaanxi, China
| | - Guanminjia Shang
- Centre for Experimental Economics in Education (CEEE), Shaanxi Normal University, Xi’an, Shaanxi, China
| | - Lei Wang
- International Business School, Shaanxi Normal University, Xi’an, Shaanxi, China
| | - Yonglei Sun
- Centre for Experimental Economics in Education (CEEE), Shaanxi Normal University, Xi’an, Shaanxi, China
| | - Annie Osborn
- Rural Education Action Program (REAP), Freedom Spogli Institute for International Studies, Stanford University, Stanford, California, United States of America
| | - Scott Rozelle
- Rural Education Action Program (REAP), Freedom Spogli Institute for International Studies, Stanford University, Stanford, California, United States of America
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Asano R, Tsuchiya KJ, Harada T, Kugizaki Y, Nakahara R, Nakayasu C, Okumura A, Suzuki Y, Takagai S, Mori N, Takei N. Season of Birth Predicts Emotional and Behavioral Regulation in 18-Month-Old Infants: Hamamatsu Birth Cohort for Mothers and Children (HBC Study). Front Public Health 2016; 4:152. [PMID: 27504441 PMCID: PMC4958653 DOI: 10.3389/fpubh.2016.00152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 07/08/2016] [Indexed: 12/04/2022] Open
Abstract
Background Previous research has demonstrated that the season of birth may predict development of emotional and behavioral regulation during childhood or adolescence. This study examined whether the season of birth predicts effortful control (i.e., the ability to voluntarily choose course of actions during conflict and to plan for the future) and aggression (i.e., the use of physical force and expression of anger toward others) in 18-month-old infants. Methods Participants included 885 infants who were enrolled in the Hamamatsu Birth Cohort for Mothers and Children in Hamamatsu, Japan. Seasons of birth were categorized into winter (December, January, and February), spring (March, April, and May), summer (June, July, and August), and autumn (September, October, and November). At 18 months of age, effortful control was assessed using the Early Childhood Behavior Questionnaire, and aggression was measured using the Cardiff Infant Contentiousness Scale. Structural equation modeling analysis with measurement and structural equations was conducted to test our prediction. Results Effortful control was higher in infants born in spring [B = 0.095, 95% CI (0.014 to 0.175), p = 0.021, β = 0.146] and summer [B = 0.078, 95% CI (0.001 to 0.156), p = 0.049, β = 0.118] than in those born in winter. In addition, aggression was lower in those born in spring [B = −0.286, 95% CI (−0.551 to −0.021), p = 0.035, β = −0.135] than those born in winter, even after controlling for seven covariates. Conclusion The findings suggest that season of birth may determine development of emotional and behavioral regulation skills during early infancy. Future research should pay more attention to the underlying mechanisms of the effects of birth season on development of emotional and behavioral regulation during infancy.
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Affiliation(s)
- Ryosuke Asano
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Kenji J Tsuchiya
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Taeko Harada
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Yumeno Kugizaki
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Ryuji Nakahara
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Chikako Nakayasu
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Akemi Okumura
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Yukiko Suzuki
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Shu Takagai
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Norio Mori
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan; Department of Psychiatry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Nori Takei
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan; Division of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
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Takagai S, Tsuchiya KJ, Itoh H, Kanayama N, Mori N, Takei N. Cohort Profile: Hamamatsu Birth Cohort for Mothers and Children (HBC Study). Int J Epidemiol 2015; 45:333-42. [DOI: 10.1093/ije/dyv290] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2015] [Indexed: 11/14/2022] Open
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Atun-Einy O, Cohen D, Samuel M, Scher A. Season of birth, crawling onset, and motor development in 7-month-old infants. J Reprod Infant Psychol 2013. [DOI: 10.1080/02646838.2013.826347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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