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Cognitive\u2013behavioural therapy (CBT), both face to face or digitally delivered, has shown to be an effective intervention for prolonged grief symptoms. Self-help mobile apps offer various advantages and studies show improved mental health after app interventions. No app has yet been evaluated targeting prolonged grief in bereaved parents. Therefore, the aim of this planned study is to develop and examine the effectiveness of a CBT-based mobile app, called\n                      <jats:italic>My Grief,<\/jats:italic>\n                      in reducing symptoms of prolonged grief, as well as other psychological symptoms, in bereaved parents. Another aim is to assess users\u2019 experiences and adverse events of\n                      <jats:italic>My Grief<\/jats:italic>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>\n                      We will conduct a two-armed randomised waitlist-controlled trial. Parents living in Sweden, who lost a child between one and ten years ago, with elevated symptoms of prolonged grief, will be recruited to participate in the trial. The content of\n                      <jats:italic>My Grief<\/jats:italic>\n                      covers four main domains (Learn; Self-monitoring; Exercises; Get support) and builds on principles of CBT and the proven-effective\n                      <jats:italic>PTSD Coach<\/jats:italic>\n                      app. Participants in the intervention group will fill out online questionnaires at baseline and at 3, 6 and 12\u2009months follow-ups, and the waitlist-controls at baseline and at 3 months. The primary outcome will be prolonged grief symptoms at the 3 months follow-up. Secondary outcomes are post-traumatic stress and depression symptoms, quality of life and cognitive behavioural variables (ie, avoidance, rumination, negative cognitions).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>Ethical approval has been received from the Swedish Ethical Review Authority (project no. 2021-00770). If the app is shown to be effective, the app will be made publicly accessible on app stores, so that it can benefit other bereaved parents.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT04552717\">NCT04552717<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2021-052763","type":"journal-article","created":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T11:26:06Z","timestamp":1638876366000},"page":"e052763","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":16,"title":["Mobile app for prolonged grief among bereaved parents: study protocol for a randomised controlled trial"],"prefix":"10.1136","volume":"11","clinical-trial-number":[{"clinical-trial-number":"nct04552717","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct04094922","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9396-9800","authenticated-orcid":false,"given":"Rakel","family":"Eklund","sequence":"first","affiliation":[{"name":"Department of Neuroscience, Uppsala University, Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maarten C","family":"Eisma","sequence":"additional","affiliation":[{"name":"Department of Clinical Psychology and Experimental Psychopathology, University of Groningen, Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul A","family":"Boelen","sequence":"additional","affiliation":[{"name":"Department of Clinical Psychology, Faculty of Social Sciences, Utrecht University, Utrecht, The Netherlands"},{"name":"ARQ National Psychotrauma Centre, Diemen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filip K","family":"Arnberg","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Uppsala University, Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josefin","family":"Sveen","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Uppsala University, Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2021,12,7]]},"reference":[{"key":"2025120521451977000_11.12.e052763.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.apnu.2005.07.008"},{"key":"2025120521451977000_11.12.e052763.2","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291704002740"},{"key":"2025120521451977000_11.12.e052763.3","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1007\/s10880-018-9590-7","article-title":"The grief of parents after the death of a young child","volume":"26","author":"Morris","year":"2019","journal-title":"J Clin Psychol Med Settings"},{"key":"2025120521451977000_11.12.e052763.4","doi-asserted-by":"crossref","first-page":"S61","DOI":"10.1097\/PCC.0000000000001466","article-title":"Caring for parents after the death of a child","volume":"19","author":"October","year":"2018","journal-title":"Pediatr Crit Care Med"},{"key":"2025120521451977000_11.12.e052763.5","doi-asserted-by":"crossref","first-page":"1530","DOI":"10.1002\/pon.5112","article-title":"Bereaved mothers\u2019 and fathers\u2019 prolonged grief and psychological health 1 to 5 years after loss \u2014 A nationwide study","volume":"28","author":"Pohlkamp","year":"2019","journal-title":"Psychooncology"},{"key":"2025120521451977000_11.12.e052763.6","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(07)61816-9"},{"key":"2025120521451977000_11.12.e052763.7","unstructured":"World Health Organization . 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