ANALISIS DAN PERANCANGAN SISTEM PAKAR BERBASIS WEB DALAM MENDIAGNOSA JENIS PENYAKIT KULIT WAJAH MENGGUNAKAN METODE CERTAINTY FACTOR

Health science continues to develop along with advances in technology, research, and increasingly in-depth scientific understanding. This development includes not only the diagnosis and treatment of diseases, but also improving prevention and overall health management. One of the conditions that is often encountered is skin disease, the symptoms of which can vary from mild to severe. The causes of skin disease vary, including poor hygiene, exposure to hazardous substances, infections, and immune disorders such as allergies. Some people consider skin care unimportant until disturbing physical symptoms appear, such as rashes, itching, or redness. Constraints such as limited doctor's practice hours, distance, and consultation costs also make people need alternative solutions for initial diagnosis. System testing was carried out by comparing the diagnosis results from the expert system with the diagnosis given by medical personnel. The test results showed that the system can provide a fairly accurate diagnosis, with a low error rate. The certainty factor method allows the system to provide predictions based on uncertainty in the answers or symptoms given. This system is expected to be an efficient solution for diagnosing facial skin diseases, helping people get initial information without having to consult a doctor directly, and supporting cost and time efficiency. Based on testing using symptom data entered by users, it shows that the system is able to provide accurate diagnosis with a success rate of 85%, while the error rate is only around 15%. This study focuses on skin diseases such as acne vulgaris, premature aging, rosacea, and dermatitis. The results of this study are expected to support the community in understanding and overcoming facial skin health problems and increasing the use of technology in web-based health services.