Insertion depth:Len:Stdy:Gastrointestinal tract.lower:Qn:Flexible sigmoidoscopy
insertion depth:len:stdy:gastrointestinal tract.lower:qn:flexible sigmoidoscopy
Insertion depth:Length:Duration of the study:Gastrointestinal tract.lower:Quantitative:Flexible sigmoidoscopy
insertion depth:length:duration of the study:gastrointestinal tract.lower:quantitative:flexible sigmoidoscopy