The aim of this study is to reduce the length of stay after liver surgery by taking account of objective quantitative clinical variables, subjective qualitative clinical variables and non clinical variables.

a new dimension of the activity expected of physicians is to improve the safety of care on the one hand and the control of health care costs on the other.

key measures to help them are the publication of national recommendations, assessment of actual practices and the incentive to activity.

Internationalwide recent and concordant data suggest that

• quality and security of care, after an initial improvement, are going to stall
• scientific recommendations are rarely validated by an impact analysis and are not applied
• clinical data collected within an administrative framework are unreliable and too generalist
• the evaluation, especially in the surgical field, is based on indicators sometimes irrelevant and often unclear

Inclusion Criteria:

• elective liver surgery
• older than 18
• agreed to participate
• surgical procedure included procedures registered as "HLFA003 - 007 ; 009 - 011 ; 017 - 020 ; HLFC002 à 004 ; 027 ; 032 ; 037" in the PMSI database

Exclusion Criteria:

• emergency surgery
• refused to participate

the population corresponds to patients operated in one of the thirteen hospitals.

These hospitals are distributed on the french territory to ensure that the recruitment is representative of the general population