RESUMO
When researchers conduct large prospective studies, they provide results generating statistical analysis; therefore readers need considerable familiarity with descriptive and inferential statistics. If quantitative judgments are based on interpreting odds ratios as though they were relative risks, they are unlikely to be seriously in error. Because of the calculating method, the OR is often less precise than the RR in estimating the strength of an association, and this should definitely be kept in mind by anyone who reads and interprets the results of a large population based-study.
RESUMO
BACKGROUND: Opioid combination has been shown to reduce the need for escalating doses for the treatment of cancer pain. A prospective study was planned to evaluate the addition of tramadol to a stronger opioid for the treatment of severe pain as a result of osteoarthritis, previously uncontrolled by non-opioid analgesics or weak opioids. METHODS: All subjects received tramadol 200 mg and tizanidine 2 mg. At 2 weeks, tramadol was discontinued for patients still reporting poor pain relief (effectiveness ≤50%), and a stronger opioid was titrated to a morphine equivalent amount (MEA) of 40-60 mg orally. After two additional weeks, patients were then divided into two groups: the Strong Opioid Group (SO) and the Tramadol plus the Strong Opioid Group (TSO). The SO group was allowed to escalate opioid dose for lack of effectiveness; the TSO group received tramadol 150 mg daily, thereafter additional strong opioid titration was allowed. RESULTS: A total of 74 patients were studied: SO (n = 40) and TSOG (n = 34). All patients eventually achieved pain relief quality, with both groups reporting similar Karnofsky Performance Scale effectiveness. The SO group achieved satisfactory pain relief (>50%) at an average daily oral MEA of 120 mg. TSO subjects achieved satisfactory pain relief (>50%) at an average daily oral MEA of 95 mg. DISCUSSION: The addition of tramadol provided a synergistic effect resulting in a 30-mg decrease in necessary morphine equivalents with fewer opioid-related adverse effects.
