The scientists studied wastewater samples from Muğla, Turkey, focusing on key characteristics like pH, temperature, and oxygen levels. They aimed to predict one important parameter, BOD5, by using data from other factors like COD and total phosphorus. Analyzing data from 334 samples, they found that COD is vital in determining BOD5 levels. If COD is low, BOD5 is likely below 100. However, high COD levels usually keep BOD5 under 200. Interestingly, when COD is in a certain range, total phosphorus becomes a crucial factor in predicting BOD5 values. The research shows how different factors in wastewater can influence the crucial BOD5 parameter.