For how many days and what types of group activities should older Japanese adults be involved in to maintain health? A 4-year longitudinal study

• Kumiko Nonaka ,

  Contributed equally to this work with: Kumiko Nonaka, Hiroyuki Suzuki

  Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Writing – original draft, Writing – review & editing

  * E-mail: nonaka@tmig.or.jp (KN); fujiwayo@tmig.or.jp (YF)

  Affiliation Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan

  http://orcid.org/0000-0002-1862-1804

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• Hiroyuki Suzuki ,

  Contributed equally to this work with: Kumiko Nonaka, Hiroyuki Suzuki

  Roles Conceptualization, Formal analysis, Methodology, Writing – original draft

  Affiliation Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan

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• Hiroshi Murayama,

  Roles Conceptualization, Formal analysis, Writing – review & editing

  Affiliations Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan, Institute of Gerontology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan

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• Masami Hasebe,

  Roles Conceptualization, Data curation, Formal analysis, Investigation, Project administration

  Affiliations Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan, Faculty of Human Welfare, Seigakuin University, Ageo-shi, Saitama, Japan

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• Takashi Koike,

  Roles Data curation, Project administration

  Affiliation Faculty of International Studies of Culture, Kyushu Sangyo University, Higashi-ku, Fukuoka, Japan

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• Erika Kobayashi,

  Roles Supervision, Writing – review & editing

  Affiliation Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan

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• Yoshinori Fujiwara

  Roles Conceptualization, Formal analysis, Funding acquisition, Methodology, Supervision, Validation, Writing – review & editing

  * E-mail: nonaka@tmig.or.jp (KN); fujiwayo@tmig.or.jp (YF)

  Affiliation Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan

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