Objective To develop a patient reported outcome instrument for chronic gastrointestinal diseases and to investigate its reliability and validity.Methods The instrument was developed by establishing item pool through interviewing typical cases

focus group discussion

expert consulting

referring to related instruments

and etc

selecting and optimizing items

small sample pilot survey

formation of primary instrument

then a multi-centered clinical investigation was conducted in Beijing

the data of 274 effective respondents of which was analyzed to assess reliability and validity using SPSS 11.5 software.Result A 6-dimention

35item instrument was developed

which has satisfying internal consistency reliability

Cronbach’s α coefficient was 0.8876

and those of all domains were more than 0.65;split-half reliability was 0.8113 and 0.8070 respectively

the correlation of two parts was 0.7058.For validity

the instrument has good discriminate validity

construct validity tested by factor analysis resulted in 6 factors with eigenvalue >1

which contributed to 52.14% of total variance

these factors can be explained as regurgitation

dyspepsia

general condition

social function

defecation and psychology.Conclusion The instrument has a good internal reliability and validity

which can be applied for the therapeutic evaluation of chronic gastrointestinal diseases

but still need further investigation and modification.