Chronic rhino-sinusitis (CRS) is a significant health problem whose incidence 
and prevalence is rising. An emphasis has been placed on diseasespecific quality 
of life (QoL as the predominant measure for most current outcome studies. 
Therefore a validated measure of health-related QoL in sinonasal disease is 
needed. The present prospective and observational study was conducted on 50 
patients in the Department of ENT at Govt. Medical College and Rajindra Hospital 
Patiala, Punjab, India. The primary outcomes were the following: (1) the chance 
of attaining minimal clinically important difference (MCID) improvements of nine 
points at the 22-item Sino-Nasal Outcome Test (SNOT-22) after endoscopic sinus 
surgery (ESS) for different preoperative QoL levels, and (2) the percentage of 
relative improvement in SNOT-22 after ESS for different preoperative QoL levels.
METHODS: Patients with CRS who were elected for ESS were prospectively enrolled 
into an observational cohort study. They were categorized into 10 preoperative 
SNOT-22 groups based on 10-point increments beginning with a score of 10 and 
ending at 110. Standard protocol for all patients presenting for evaluation 
included completion of the SNOT-22 prior to and following surgical intervention. 
The scores were calculated and the data collected were compiled and analyzed.
RESULTS: A total of 50 patients were included in this study. Patients with a 
SNOT-22 score between 10 and 19 had the lowest chance of achieving an MCID. 
Patients with a SNOT-22 score greater than 30 had a greater than 90% chance of 
achieving an MCID, and there was a relative improvement of 43.3% on their 
preoperative SNOT-22 scores. CRS patients with polyp had better outcomes (47.1% 
improvement) after ESS than those without polyp (33.2% improvement).
CONCLUSION: There is an increased probability of achieving an MCID at SNOT-22 
score >30 and in general the percentage of relative improvement increased with 
an increase in preoperative SNOT score.