がん患者の抑うつ状態を早期発見するためのアセスメントツールの開発

Development of An Assessment Tool for Early Detection of a Depressive State in Patients with Cancer

要旨

目的：がん患者の抑うつ状態を早期発見するためのアセスメントツールを開発する．

研究方法：研究倫理審査委員会の承認を得て実施した．アセスメントツール（以下，AT）28項目は文献から選定し，DSM-Ⅳ-TR大うつ病エピソードとの適合を検討した．内容妥当性を，がん看護または精神看護専門看護師5名を対象にした修正デルファイ法で確認した．パイロットスタディ（以下，PS）で評定者間一致率を，本調査で項目選定，構成概念妥当性，基準関連妥当性および内的整合性を確認した．がん治療目的で入院している20歳以上の患者に対し，看護師は日勤帯に7日間，ATを用いて評価した．基準関連妥当性の確認のために患者にはBDI-Ⅱの記載を依頼した．

結果：修正デルファイ法の結果，ATは24項目となり，4段階評価に1〜4点の得点を付した．PSで患者27名を15名の看護師がATを用いて評価し，評定者間一致率は93〜100％であった．本調査では377名の患者を79名の看護師がATを用いて評価した．項目選定分析で21項目となり，検証的因子分析による適合度指標はGFI＝0.768，α係数は0.932であった．BDI-Ⅱ重症度分類別のAT合計得点に有意な差を認め（p＜0.05），基準関連妥当性を確認した．

考察：開発したATの内容妥当性，評定者間信頼性，構成概念妥当性，信頼性および基準関連妥当性が確認できたが，重症度を判別する精度が課題となった．

Objective: The purpose of this study was to develop an assessment tool for early detection of depressive states in patients with cancer.

Method: The study was approved by the ethics board of the affiliated university. For the assessment tool (AT), 28 items were developed based on a comprehensive review of the literature and the criteria for major depressive episodes according to the DSM-IV-TR. Content validity was confirmed with a three-round, modified Delphi technique administered to certified nurse specialists in cancer nursing or psychiatric mental health nursing in Japan. Inter-observer reliability was assessed in a pilot study. Item analysis, reliability, and validity were assessed in the main survey. Severity of AT scores was based on the severity of BDI-II scores. Nurses estimated depression severity using the AT for 7 days during day shifts, and patients were asked to use the BDI-II.

Sample: The pilot study was conducted with 27 diagnosed cancer patients and 15 nurses, and the main survey was conducted with 377 diagnosed cancer patients and 79 nurses.

Result: 1）The AT consisted of 24 items as a result of the literature review, according to the DSM-IV-TR major depressive episode definition, and the modified Delphi technique. 2）The inter-observer concordance rate was 93-100％. 3）Item analysis resulted in 21 final items. 4）A confirmatory factor analysis yielded a GFI of 0.768. The reliability of the AT was confirmed by a Cronbach's alpha internal consistency reliability coefficient of 0.932. A significant difference in severity classification between the BDI-II score and AT score (p<0.05) was found.

Conclusion: The above findings indicate that the developed AT had content validity, interrater reliability, construct validity, reliability, and criterion-related validity. The subject of the next investigation will establish whether the AT can distinguish the severity of depression.