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Snot 22 Score Calculator

Calculate the Sino-Nasal Outcome Test score for chronic rhinosinusitis assessment. Enter values for instant results with step-by-step formulas.

Reviewed by Rahul Singh, Health & Wellness Specialist

Reviewed by Rahul Singh, Health & Wellness Specialist

Formula

SNOT-22 = Sum of 22 items (each scored 0-5)

Each of the 22 items is scored from 0 (no problem) to 5 (problem as bad as it can be). Total score range: 0-110. Scores > 7 are above normal. MCID (minimal clinically important difference) is 8.9 points. Four domains: rhinologic (items 1-8), extra-rhinologic (9-12), sleep (13-17), psychological (18-22).

Worked Examples

Example 1: Pre-Surgical CRS Assessment

Problem:A patient with CRS with nasal polyps rates their symptoms before endoscopic sinus surgery. Key scores: nasal obstruction 5, loss of smell 5, thick discharge 4, post-nasal drip 3, fatigue 4, poor sleep 3, reduced concentration 3. Other items average 2.

Solution:High-scoring items: 5+5+4+3+4+3+3 = 27\nRemaining 15 items at average 2: 15 x 2 = 30\nTotal SNOT-22 = 27 + 30 = 57/110\nRhinologic domain heavily affected\nSleep and psychological domains moderately affected

Result:SNOT-22: 57/110 | Severe | Strong surgical candidate - expected improvement of 20-25 points post-ESS

Example 2: Post-Treatment Follow-Up

Problem:Same patient returns 6 months after surgery. Scores: nasal obstruction 1, loss of smell 2, thick discharge 1, post-nasal drip 1, fatigue 1, poor sleep 1, reduced concentration 1. Other items average 0.5.

Solution:Key items: 1+2+1+1+1+1+1 = 8\nRemaining 15 items at average 0.5: 15 x 0.5 = 7.5 (round to 8)\nTotal SNOT-22 = 8 + 8 = 16/110\nImprovement: 57 - 16 = 41 points\nMCID = 8.9 points\nImprovement far exceeds MCID

Result:SNOT-22: 16/110 | Mild | Improvement of 41 points (exceeds MCID of 8.9) - excellent surgical outcome

Frequently Asked Questions

What is the SNOT-22 and what does it measure?

The Sino-Nasal Outcome Test 22 (SNOT-22) is the most widely used and validated patient-reported outcome measure for chronic rhinosinusitis (CRS). It was developed as an expansion of the earlier SNOT-20 by adding two questions about loss of smell/taste and nasal obstruction, which are critical symptoms of CRS that the original instrument failed to capture. The SNOT-22 consists of 22 questions spanning four domains: rhinologic symptoms (nasal and sinus symptoms), extra-rhinologic symptoms (ear and facial symptoms), sleep dysfunction, and psychological dysfunction. Each question is scored from 0 (no problem) to 5 (problem as bad as it can be), giving a total score range of 0 to 110.

What SNOT-22 score is considered abnormal?

A SNOT-22 total score above 7 is generally considered above the normal range for the healthy population. Studies of healthy control subjects without sinus disease report mean SNOT-22 scores of approximately 7 to 9 points. Scores of 8 to 20 indicate mild symptom burden, scores of 21 to 50 indicate moderate symptoms, and scores above 50 indicate severe disease with significant quality-of-life impairment. However, these severity categories are approximate guides rather than rigid classifications. The mean preoperative SNOT-22 score for patients undergoing endoscopic sinus surgery is typically 42 to 55, indicating that most surgical candidates have moderate to severe symptom burden. Individual item analysis can reveal which specific symptoms are most bothersome.

What is the MCID for the SNOT-22?

The minimal clinically important difference (MCID) for the SNOT-22 total score is 8.9 points, as established by Hopkins and colleagues in 2009. This means that a change of 9 or more points in the total SNOT-22 score represents a difference that patients can perceive as a meaningful improvement or worsening in their condition. The MCID is critical for interpreting treatment outcomes because statistically significant changes may not always be clinically meaningful. When evaluating the success of medical or surgical treatment, clinicians should look for an improvement of at least 8.9 points rather than simply checking for statistical significance. Individual domain MCIDs have also been established but are used less frequently in clinical practice.

How is the SNOT-22 used before and after sinus surgery?

The SNOT-22 is a standard outcome measure used to evaluate the effectiveness of endoscopic sinus surgery (ESS) for chronic rhinosinusitis. It is administered preoperatively to document baseline symptom severity and postoperatively (typically at 3, 6, and 12 months) to quantify improvement. Large prospective studies have shown that ESS produces an average SNOT-22 improvement of 20 to 25 points, with approximately 75 to 85 percent of patients achieving an improvement exceeding the MCID of 8.9 points. The SNOT-22 is also used to identify which patients are most likely to benefit from surgery, as those with higher preoperative scores tend to show greater absolute improvement. Surgeons and insurers increasingly use SNOT-22 scores to help justify surgical intervention.

References

Reviewed by Rahul Singh, Health & Wellness Specialist · Editorial policy