FIELD : medicine.SUBSTANCE : invention refers to medicine, particularly to gastroenterology, and can be used as an express diagnostic technique for gastroesophageal reflux disease (GERD). A method involves examining a patient by testing, analyzing the values obtained during testing, calculating the values of said indices and diagnosing the presence or absence of gastroesophageal reflux disease in the patient with further recommendations on further treatment and examination of the patient. A patient is examined for the following values, which are considered as binary values and evaluated as "0" with a negative response and "1" with a positive response : smoking (x1), presence or absence of heartburn (x2), frequency of heartburn at least 2 times a week (x3), belching liquid (x4), difficulty in swallowing any food (x5), bitter taste in mouth (x6), sour taste in mouth (x7), burning and chest pain (x8), pain under the xiphoid process shortly after eating, increasing with inclinations (x9), sore throat (x10), hoarse voice in the morning (x11), night dry cough more than 1 year (x12) runny nose, not associated with cold and lasting for more than 6 months (x13), discomfort in tongue (x14), mouth sores (x15), difficult breathing (x16), administration of non-steroidal anti-inflammatory drugs (x17), broncholytics (x18), administration of antihypertensive agents (x19), frequent or prolonged stress (x20), lifting and carrying weights (x21), frequent or prolonged torso inclination (x22), muscular spasm at palpation of back muscles (x23), body weight index more than 25 (x24). Calculation is carried out based on the following relationship : Y= - 25.9317 + 0.4449x1 + 22.4596x2 + 9.1589x3 + 35.6102x4 + 7.0517x5 + 8.243x6 + 12.8106x7 + 27.2946x8 + 12.4076x9 + 24.4989x10 + 2.7262x11 - 16.6957x12 + 17.9306x13 - 8.5624x14 - 11.318x15 + 0.9758x16 + 43.892x17 + 7.2807x18 + 3.9544x19 - 44.1693x20 + 47.6006x21 - 45.6792x22 + 3.7975x23 - 44.7048x24. If Y0.5 shows a gastroesophageal reflux disease.EFFECT : method enables detecting GERD at an early stage by evaluating a complex of the most significant indicators.1 cl, 2 ex