Author contribution / 論文著者の役割

投稿規定に導入されている雑誌も多いですが、
ICMJE( International Committee of Medical Journal Editors)の下記ページが参考になります。
http://www.icmje.org/recommendations/browse/roles-and-responsibilities/defining-the-role-of-authors-and-contributors.html

これをみると、

1. Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; AND  
2. Drafting the work or revising it critically for important intellectual content; AND  
3. Final approval of the version to be published; AND  
4. Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.  

とありますので、

1で構想・デザイン・データの取得・分析・解釈のうち1つ以上、

2で筆頭などはdraft、それ以外の著者はrevising

3, 4 は全員

最低限満たすかどうかが、著者の判断基準になるでしょう。