Another widely used tool is the Brief

Another widely used tool is the Brief Pain Inventory (BPI), developed by Cleeland and Ryan. The BPI is a questionnaire used to determine overall pain intensity and functional interference as a result of pain. Specifically, it GW5074 examines functional interference in terms of general activity, normal work, walking ability, mood, sleep, relations with others, and enjoyment of life [6]. In addition, it captures three aspects of pain: worst, average, and current intensity. Finally, the Edmonton Symptom Assessment System (ESAS) examines symptoms on a scale of 0, representing ‘absence of symptom’ to 10, representing ‘worst possible symptom’ [14]. Symptoms captured in this questionnaire are pain, tiredness, nausea, depression, anxiety, drowsiness, appetite, feeling of well-being, and shortness of breath. In general, symptoms given a rating of 1–3 are considered mild, 4–7 are considered moderate, and 8–10 are considered severe [14].
Methods
Results The literature search resulted in a total of 1730 articles. Eighteen of these articles, published between 1977 and 2013, met the eligibility criteria [1,3,4,7,8,11–22]. All studies collected data prospectively, except for that by Gilbert et al. [20] who determined QOL through chart review. Only 3 of the studies were randomized control trials [3,21,22], while the rest employed no other intervention than the questionnaire. The most commonly used tool was the BPI, used in a total of six papers [1,4,10,11,15,16]. The next most commonly used assessment tools were EORTC measures and the ESAS, which were employed in five [7,12,13,18,19] and three [8,14,17] studies, respectively. Other assessment tools included the Patient-Generated Subjective Global Assessment, net pain relief, the McGill–Melzalk Score, the Spitzer scale, and others [3,20–22]. In total, eight articles [1,4,7,10,12,15,16,18] directly compared QOL in responders and non-responders, as defined by the International Bone Metastases Consensus guidelines, while the remaining ten [3,8,11,13,14,17,19–22] made no differentiation between the two patient groups.
Discussion As a multidimensional concept that encompasses the well-being of the whole person, QOL is both difficult to define and measure. Often, bone metastases cause pain which decreases mobility and interferes with physical functioning. In turn, this may lead to an inability to seek support from friends and family, causing emotional and psychological distress. In an article written by Carlson et al. [23], distress was defined as “normal feelings of vulnerability, sadness, and fears, to problems that can become disabling such as depression, anxiety, panic, social isolation, and spiritual crisis”. These authors stated that distress is associated with reduced survival and QOL, and that both pain and fatigue are highly validated components of distress. This was further confirmed in a study conducted by Kaasa et al. [24], who showed that psychological distress is related to pain and reduced performance status. Currently, treatment response is defined by the International Bone Metastases Consensus guidelines in terms of pain score and analgesic consumption [25]. It is hypothesized that, if psychological distress is related to pain and reduced performance status, an improvement in pain will lead to an improvement in psychological aspects of one׳s health and QOL. Our literature review confirmed that the majority of patients experience an improvement in QOL following RT; however, it is unknown which aspects of QOL improve, and the degree to which this improvement is related to pain response. Only three of the 18 studies were randomized control trials [3,21,22], all of which were exploring the use of fractionation schedule and radiation technique. Numerous other randomized control trials have investigated similar questions; however their primary endpoints are often pain score, survival, and toxicity. It is important for the endpoints of these randomized control trials to be reconsidered to include QOL because its maintenance or improvement is such a vital goal of palliative treatment.