2.4. Randomization, Blinding, and the Study Protocol

All participants were assigned to either study group at a 1:1 ratio using computer-generated blocks of four randomization sequences. A trial identification number was used to identify each participant, and the assignment of treatment code was performed. Participants and investigators were all blinded to the group allocation. However, the pharmacists who prepared the sachets were exposed to the allocation. Participants in the intervention group received one sachet of multispecies probiotics per day, which could be taken orally before any meal for 12 weeks. Each sachet taken by the intervention group contains Lactobacillus reuteri GL-104 1.5 Billion CFU, Lactobacillus paracasei MP-137 0.6 Billion CFU, Lactobacillus rhamnosus MP108 0.6 Billion CFU, Lactobacillus rhamnosus F-1 0.3 Billion CFU, Lactobacillus rhamnosus BV77 0.6 Billion CFU, Bifidobacterium animalis ssp. lactis CP-9 2.4 Billion CFU, Bifidobacterium longum ssp. longum OLP-01 1 Billion CFU, Bacillus coagulans 1 Billion CFU, and 270 milligrams of inulin (prebiotics) (CMED PRODUCTS 1994 Company Limited, Bangkok, Thailand). In contrast, participants allocated to the placebo group received sachets produced with the same size, shape, odor, color, and packaging as the probiotic sachets but contained only 270 milligrams of inulin. Similar to the intervention group, participants could take one sachet per day orally before any meal. Participants in both groups received at least 1200 milligrams of calcium daily and 20,000 IU of vitamin D2 per week. Although they were asked to avoid food, beverages, or supplements containing probiotics, such as yogurt and kimchi, during the study, usual medications for their underlying diseases could still be taken. In addition, they were encouraged to perform routine daily activities, including their lifestyle, diet, and exercise.