The goal of this observational study is to explore the correlation between the difficulty of colonoscopy and the patients' personality in the population receiving initial colonoscopy in Peking Union Medical College Hospital. The main question it aims to answer is: Whether the difficulty of colonoscopy is related to any personality score of big five personality dimensions

Participants will:

1. Receive routine colonoscopy
2. Fill out the GAD-7 and PHQ-9 scales
3. Fill out the Big Five Personality Questionnaire.

Colonoscopy as an invasive test may cause pain, discomfort and anxiety to the patient . Insertion time and patient pain scores are indicators of the degree of colonoscopy difficulty, with the incidence of difficult colonoscopy being approximately 25% . It is usually defined as a difficult colonoscopy when the insertion time is more than 10 minutes. Several studies have shown that certain risk factors can help us predict the occurrence of difficult colonoscopy, such as gender, age, BMI, bowel preparation, and history of abdominal or pelvic surgery .

In addition to the objective factors mentioned above, the patient's personality, mood and psychological state may also have an impact on the difficulty of colonoscopy. In clinical practice, endoscopists have observed that patients with anxiety-prone or obsessive personalities tend to have a higher incidence of difficult colonoscopies, but few studies have explored the predictive role of patient personality on the degree of difficulty in colonoscopy. In addition, because personality stability may be influenced by anxiety and depression levels as well as specific strong situations, the patient's recent anxiety and depression levels should also be taken into account. We therefore used the Generalized Anxiety Scale (GAD-7) and the 9-item Patient Health Questionnaire Depression Scale (PHQ-9) to assess patients' recent levels of anxiety and depression, respectively.

The Big Five is currently recognized as the most comprehensive model of personality analysis and has been widely used in clinical and scientific research. The Big Five includes extraversion、extraversion、conscientiousness、neuroticism、openness. This study intends to use the Chinese version of the Big Five Personality Questionnaire to test the scores of patients in the five personality dimensions, in order to observe whether the difficulty of colonoscopy is related to the scores of any personality dimension.

Inclusion Criteria:

1. Age 18-75 years old
2. Patients or family members were able to understand the study protocol and willing to participate in this study by signing informed consent.
3. Those who underwent colonoscopy at the Gastrointestinal Endoscopy Center of Peking Union Medical College Hospital.

Exclusion Criteria:

1. Patients who have taken colonoscopy before
2. Patients who are unable to read or write
3. Patients with severe mental disorders, organic brain mental disorders
4. those with poor bowel preparation (BBPS < 6 )
5. patients with chronic constipation, history of intestinal diverticula
6. Patients who have undergone previous colorectal surgery
7. those with previous findings of severe colonic strictures or obstructive tumors
8. patients who are pregnant or breastfeeding
9. patients with severe infectious diseases.
10. Patients with inflammatory bowel disease, familial polyposis.

People who meet the eligibility criteria and undergo colonoscopy at Peking Union Medical College Hospital.