2.1 Reliability of Aberdeen Low Back Pain Scale
With the significance of Aberdeen Low Back Pain Scale in the treatment assessment for the low back pain patient, it is rather subject to reliability concerns (Ruta et al., 1994). Kreitler& Beltrutti (2007) have found high reliability of Aberdeen Low Back Pain Scale, as it is simple while lack of repetition in questionnaires yields a reliability coefficient of .83. Similarly, Morris (2005) has also found high reliability of Aberdeen Low Back Pain Scale by comparing it to Oswetry Waddell and its main subscales including physical and psychosocial dimensions. He found that Aberdeen Low Back Pain Scale correlated better than the overall Oswetry Waddell that is .85 to the physical dimensions. On the other hand, he has found low reliability of Aberdeen Low Back Pain Scale in the comparison with psychosocial dimensions of Oswetry Waddell that is (.59) Aberdeen Low Back Pain Scale to the Oswetry Waddell (.88). Professional academic writing services uk.
Measuring the reliability of the Aberdeen Low Back Pain Scale is due to estimating the magnitude error for analyzing the appropriateness of the measurements regarding application to particular task and to determining the consistency in the measurement to introduce more improvement. Therefore, repeatability and reproducibility studies have been conducted in literature to evaluate the tools. Reproducibility has been demonstrated while studying two groups of patients, amongst which the first group reported no clinical changes and second groups reported no continuation to full activities. Thus, test-retest results showed correlations above .80 for the first group while .76 for the second group. The outcomes of the study showed that Aberdeen Low Back Pain Scale is as reliable as Oswetry Waddell while in some cases it is stronger outcomes tool than the Oswetry Waddell. Therefore, Morris (2005) concluded that Aberdeen Low Back Pain Scale is as valid as the lengthier Oswetry Waddell tool.
Furthermore, to justify the reliability of Aberdeen Low Back Pain Scale over Oswetry Waddell, Hartigan, Rainville, Sobel, and Hipona (2000) have conducted a comparative research in which they found that condition-specific Aberdeen Low Back Pain Scale has more advantage over Oswetry Waddell. They have concluded that this advantages is due to its reliability, which includes brevity (19 vs. 136 items), correlation to physical dimension of the Oswetry Waddell and less susceptible changes to psychosocial function than physical function. According to them, these features of Aberdeen Low Back Pain Scale increase the reliability of the outcomes taken by Aberdeen Low Back Pain Scale when evaluating the low back pain population (Hartigan, Rainville, Sobel& Hipona, 2000). Best dissertation writing help.
In order to determine the reliability of the Aberdeen Low Back Pain Scale, Davidson and Keating (2002) conducted a comparative study, in which they compared five different low back questionnaires including Aberdeen Low Back Pain Scale original versions. Davidson and Keating found that the reliability of Aberdeen Low Back Pain Scale measurements tool was low, with an intra-class correlation coefficient equal to (ICC[2,1]) of .53 (95% confidence interval[CI]=.29,.71) for the population of 47 patients with low back pain who stated that their clinical condition was“about the same,”“a little better,” and“a little worse.” Moreover, the smaller subgroups reported their low back pain as“about the same” in which the ICC (2, 1) was lower at .42. Analyzing the findings of the study, the study has reported low Aberdeen Low Back Pain Scale with lack of sufficient reliability and scale width for the clinical condition.
The findings of the study, conducted by Davidson and Keating (2002), have been found quite different from the findings of other study reported in the literature on the reliability of the Aberdeen Low Back Pain Scale measurement tool. However, for the level of difference in the findings have been justified by sample difference in the study, as the sample of study conducted by Davidson and Keating consists of patients with self-referred for the physical therapy whereas these patients increased the variability, causing the low reliability of the Aberdeen Low Back Pain Scale tool (Ranieri et al., 2009). In addition, the low reliability of Aberdeen Low Back Pain Scale reported by Davidson and Keating is tended to be because of random variation related to making appoint estimate including ICC. A point estimate is found as single value while a confidence interval shows range of possible values. Thus, the upper bounds of the 95 percent correlation indices reported by Davidson and Keating are .71 and higher for the Aberdeen Low Back Pain Scale. Hire assignment writing services.
Since, correlation indices of reliability that is intra-class correlation coefficients demonstrate the mistake in the measurements, as a proportion of the sum variance in scores. These are influenced by sample variance and inconsistency in measurements; therefore, it is justified that the findings of the Davidson and Keating could have error in depicting the reliability of the Aberdeen Low Back Pain Scale tool. On explaining the reasons of low reliability of Aberdeen Low Back Pain Scale in the study of Davidson and Keating, it is found that the questions in the Aberdeen Low Back Pain Scale require the subjects that apply“today”, whereas low back pain may vary from day to day. Therefore, if the duration of the study is six weeks, there is more probability that total rating of change occurs in specified time only (Muller et al., 2004).
2.2 Validity of Aberdeen Low Back Pain Scale
The validity of Aberdeen Low Back Pain Scale instrument shows the ability of the tool to measure what it is intended to measure (Kopec& Esdaile, 1995). Moreover, the most important proeperties of Aberdeen Low Back Pain Scale in measuring the treatment effectveness include content- construct and criterion-related validity, responsiveness and effectiveness. However, the responsiveness is the ability of the Aberdeen Low Back Pain Scale to identify the clinically significant changes in the construct being measured. Frost, Lamb, and Shackleton (2000) have found Aberdeen Low Back Pain Scale as giving valid outcomes in their comparative study with other measurement tools. Moreover, in terms of comparing the validity of Aberdeen Low Back Pain Scale against other tools, they found that there is moderate correlation between the Aberdeen Low Back Pain Scale, DRI and WDI, which have shown 0.74 and 0.63 respectively. They have further indicated that Aberdeen Low Back Pain Scale correlated moderately with the Visual Analogue Scale (VAS) for pain for which Aberdeen Low Back Pain Scale is found 0.63 (Frost et al., 2000). On the other hand, a comparative study conducted by Faas, van Eljik, Chavannese, and Gubbels(1995)evaluated content validity and construct validity of Aberdeen Low Back Pain Scale to identify if the questionnaire is able to accurately measure the person’s changes in disability in daily activities because of low back pain. They reported that the validity of Aberdeen Low Back Pain Scale is constraints because of different reasons such as it merely incorporates particular physical problems of subject and does not include the psychological as well as social problems (Fass et al., 1995), in addition, in many studies, the data for Aberdeen Low Back Pain Scale are presented. With regard to construct validity of Aberdeen Low Back Pain Scale, Faas, van Eljik, Chavannese, and Gubbels have found the Aberdeen Low Back Pain Scale more effective in validity, as it correlates well with other tests which measure physical disability such as physical subscale of SG-36, Pain Rating and Quebec Low Back Scale (Fass et al., 1995). Moreover, Dionne, Koepsell, Von Korff, Deyo, Barlow, and Checkoway (1997) reported the construct validity of Aberdeen Low Back Pain Scale against other tool including Sickness Index Profile, Quebec Back Scale, Oswestry Disability Index and SC56 as high. Get uk essay writing service.
Moreover, in order to measure the validity of Aberdeen Low Back Pain Scale in terms of responsiveness, Patrick, Deyo, Atlas, Singer, Chapin, and Keller (1995) conducted a comparative study for identifying the internal as well as external responsiveness of Aberdeen Low Back Pain Scale. In this view, they found that the internal responsiveness level of Aberdeen Low Back Pain Scale, which was aimed at showing the ability of the test to measure difference in time, vary from others such as Aberdeen Low Back Pain Scale 19 items ranges from 0.63 to 0.71, other 18-items ranges from 0.7 to 0.82 while 11-item ranges from 0.61 to 0.69 (Patrick et al., 1995). On the other hand, study conducted by Muller, Duetz, Roeder, and Greenough (2004) reported that known floor effects were not present however; the ceiling effects were present in the findings of the study. Besides, the effects size measures the practical importance related to the strength between variables. In addition, Faas, van Eljik, Chavannese, and Gubbels (1995) compared the findings of the Aberdeen Low Back Pain Scale and ODI for evaluating the validity of both tools and they found that their comparison had been difficult because there were distinct measurements of validity. However, Mulleret al, (2004) found that ceiling effects were present in the Aberdeen Low Back Pain Scale while ceiling effects were absent in ODI and floor effects were present in the ODI but not in the Aberdeen Low Back Pain Scale.
The ceiling effects in this comparative study means that the measurement could not go above the limit or ceiling point that takes place because of the measurement tool itself. The study of Faas, van Eljik, Chavannese, and Gubbels (1995) also revealed that comparing both measurement tools, there has been one consistency between the validity score of both assessment questionnaires that is the construct validity, which is highly correlated with other study. Thus, from the test-retest in the study, it is found that validity is high in Aberdeen Low Back Pain Scale and in the ceiling and floor effects; the Aberdeen Low Back Pain Scale has the subject scoring higher in the upper level of the distribution other than in the top half of the ODI (Fass et al., 1995). In addition, Aberdeen Low Back Pain Scale can be used for the clinical purpose to provide guide decision-making, as it provides valid information that is clinically relevant and applicable.
Another study, conducted by Diolle, Koepsell, Von Korffm Deyo, Barlow, and Checkoway (1997), found content validity of Aberdeen Low Back Pain Scale in the context of nature of questions asked in the questionnaire. To describe the validity of Aberdeen Low Back Pain Scale, the study found that the questionnaire only focuses on the limited range of physical functions such as walking, bending, sitting, lying and dressing while has ignored numbers of other activities. According to them, the absence of important physical function decreases the validity of the questionnaire, as the questionnaire is unable to measure the person’s all physical disabilities (Dionne et al., 1997). In addition, assessing the validity of the measurement, they have reported that questionnaire contains the questions as functions that are relevant to all patients with low back pain; therefore, the scoring system in the tool does not allow a non-applicable response (Dionne et al., 1997). According to Kopec, Esdaile,& Abrahamowicz (1996), the instruments such as Aberdeen Low Back Pain Scale considerably lacks strong conceptual foundation and therefore, it has uncertain content validity. buy coursework online
2.3 Sensitivity of Aberdeen Low Back Pain Scale
It has been observed that the Aberdeen Low Back Pain Scale is most sensitive for the patients with mild to moderate chronic low back pain. According to the research conducted by Resnik and Dobrykowski (2005), the sensitivity of Aberdeen Low Back Pain Scale depends on the initial score of patients are either below 0 or above 0. Furthermore, Hodselmans, Dijkstra, Geertzen, Preupert, and Van der Schans (2010) identified that the Aberdeen Low Back Pain Scale has been found sensitive in patients with chronic low back pain with the ages of 34 to 36. Research conducted by Machado, Kamper, Herbert, Maher, and McAuley (2009) provided that the Aberdeen Low Back Pain Scale was found to be crucial instrument, which was used to assess the outcomes, which are sensitive enough to detect small changes with the passage of time. Deyo (1995) conducted a research on the responsiveness of Aberdeen Low Back Pain Scale and analyzed the sensitivity of the tool using a stricter cut-off with a score of 5 indicating improved and a score of 20 or more indicating not improved. They also analyzed the less strict cut-off for the sensitivity of Roland Morris Disability Questionnaire with a score of 3 or greater indicating improved and a score of 2 or less indicating not improved.
Waddell (1996) determined that the score of Aberdeen Low Back Pain Scale was based on the frequency of numbers that were provided by the patients with chronic low back pain and the scores ranged from 0 with no back pain related activity limitation to 100 with severe back pain related activity limitation. From this study, it was observed that the Aberdeen Low Back Pain Scale reflected meaningful clinical sensitivity when repeated measures of the test exceed±4/24 and it reflected to be the most sensitive for detecting the clinically important change for the patients of chronic low back pain (Waddell, 1996). Experienced thesis writers are available online.
However, the study by Ijzelenberg and Burdorf (2004) provided that the Aberdeen Low Back Pain Scale is not sufficiently sensitive to measure the changes in the treatment of patients with low back pain. Moreover, they argued that the Aberdeen Low Back Pain Scale is not adequate to use as the evaluative outcome measure in the individual patients with the initial score less than six because such patients with chronic low back pain cannot improve (Ijzelenberg& Burdorf, 2004). According to Terwee, Bot, Boer, Windt, Knol, Dekker, Bouter, and Vet (2007), the responsiveness of Aberdeen Low Back Pain Scale indicates the sensitivity of questionnaire for measuring the true change in patients of chronic low back pain. On the other hand, in the study conducted by Pengel, Refshauge, and Maher (2004), it has been highlighted that the numeric form of responses from 0 to 100 is less likely sensitive in Aberdeen Low Back Pain Scale as compared to the five point scale or the eleven point scale.
It has been identified in the study of Jacob, Baras, Zeev, and Epstein (2001) that the sensitivity of Aberdeen Low Back Pain Scale has been developed with the patients of chronic low back pain along with the patients suffering from heterogeneous chronic pain. Furthermore, according to Bombardier, Hayden, and Beaton (2001), it has been found that the participants of Aberdeen Low Back Pain Scale test will complete a number of functional low back pain outcome measures with the primary outcome measure accepted as valid and a sensitive measure of functional outcome specific to the condition among the patients with chronic low back pain. Thus, Aberdeen Low Back Pain Scale is considered as the preferred instrument for assessing and evaluating the change in the patients with chronic low back pain due to implementation of interventions over certain time (Bombardier et al., 2001). The findings of the study conducted by Jarvik, Kallmes, and Mirza (2003) revealed the relevancy in such a way that the Aberdeen Low Back Pain Scale is sensitive to change across time and correlates with the level of low back pain of the patient.
Many researches and studies on the Aberdeen Low Back Pain Scale highlighted the sensitivity of the tool as compared to other measurement tools being used in the clinical practice. The sensitivity of Aberdeen Low Back Pain Scale reflected that the results and measures of the patients with the chronic low back pain changes with the passage of time. Moreover, it has been further observed that the other popular tools such as Oswetry Disability Index in comparison to Aberdeen Low Back Pain Scale are not sensitive to the passage of time and specific conditions for which they are being used. Therefore, it can be said that the Aberdeen Low Back Pain Scale is the sensitive tool for measuring the change in patients of chronic low back pain because many studies in this section of the paper has provided evidences. case study writing service
2.4 Specificity of Aberdeen Low Back Pain Scale
Responsiveness has been found as significant measurement feature while evaluating the effectiveness of self-report disability scale and from this point of view, two important properties of responsiveness are sensitivity and specificity. Hartigan, Rainville, Sobel, and Hipona (2000) in their study found high specificity percentage of Aberdeen Low Back Pain Scale. They found that the properties of measurement of Aberdeen Low Back Pain Scale contain specificity, as questionnaire holds the better measurement properties and based on the result, it is found that the optimal cutoff point of the measurement tool decreases the total error is 3.5 with specificity 88.2% (Hartigan et al., 2000). On the other hand, Fisher& Johnston (2002) found low specificity in Aberdeen Low Back Pain Scale because of lack of potential of the questionnaire to be applicable in all low back pain situations. Stratford, Binkley, and Riddle (1998 ) have found the Aberdeen Low Back Pain Scale with lack of specificity particularly in patients with acute low back pain, as the measurement tool detects the change where no clinically conceptual change has taken place based on the external standards.
In this regard, Souza (2008) found high specificity percentage of Aberdeen Low Back Pain Scale, in which the test scored as positive or negative depending on the cutoff values causing overall score ranging from 0 to 100. Moreover, the higher values represented the increased levels of the physical impairment in the study. Waddell, Somerville, and Henderson (1992) found Aberdeen Low Back Pain Scale reliable in terms of specificity, which yielded result values as .86 and .95. In addition, the study found clear distinction between patient with low back pain and patient without any symptoms and showed 86% specificity. Deyo (1995) conducted study to have measured the specificity of Aberdeen Low Back Pain Scale through evaluating the properties of the Aberdeen Low Back Pain Scale and they have found the Aberdeen Low Back Pain Scale as acceptable scale for measuring the disability related to low back pain. The study conducted by Deyo (1995) assessed the six time intervals and studied the length of test interval between T-1 and T0 and T1. The analysis of the effects of parameters on the responsiveness as well as interpretability was based on Aberdeen Low Back Pain Scale score changes. In addition, agreement parameters descended as the interval time between test-retest increased. Morris (2005) conducted study on the responsiveness of patients to Aberdeen Low Back Pain Scale to identify the specificity of the scales through assessing the ability of the Aberdeen Low Back Pain Scale to discriminate between clinically relevant and clinically irrelevant changes. He found false positive for each of various cut-off points in the score change (Morris, 2005).
2.5 Strengths and Weaknesses of Aberdeen Low Back Pain Scale
2.5 (a) Strengths of Aberdeen Low Back Pain Scale
It has been identified from the previous researches and studies that the original tool Aberdeen Low Back Pain Scale is strong over other assessment tools. According to Stratford, Binkley, Solomon, Gill, and Finch (1994), the Aberdeen Low Back Pain Scale is short, simple to complete and easily understood by the patients with chronic low back pain. However, Farrar, Young, LaMoreaux, Werth, and Poole (2001) indicated that the most profound benefit of Aberdeen Low Back Pain Scale is the capability of tool for modifications in the original version with the help of translations in different languages. Furthermore, the scores of Aberdeen Low Back Pain Scale reported in a wide variety without correlating to the age or gender of the respondents suffering from chronic low back pain having chronic low back pain. The Aberdeen Low Back Pain Scale mainly focuses on the range of physical functions of patients with chronic low back pain, which includes walking, sitting, dressing, sleeping, and daily activities (Costa et al., 2009). Get research paper writing help
According to Morris (2005), it has been revealed that the Aberdeen Low Back Pain Scale is correlated to the physical dimension as compared to Oswerty Waddell. The Aberdeen Low Back Pain Scale has content and constructs validity because it is sensitive as well as reproducible to change with the passage of time for the patients of chronic low back pain (Solberg et al., 2005). Additionally, it has been observed from the research of Kamper, Maher, Herbert, Hancock, Hush, and Smeets (2010) that Aberdeen Low Back Pain Scale accurately classifies the recovery of patients from chronic low back pain.
2.5 (b) Weaknesses of Chronic Low Back Pain Scale
It has been observed that the Aberdeen Low Back Pain Scale did not compare with the psychosocial dimension to the Oswerty Waddell and other tools. However, it can be said that the Aberdeen Low Back Pain Scale is not useful in patients of chronic low back pain with the baseline value below the six points because Aberdeen Low Back Pain Scale is not easy to evaluate the change, which is clinically important for the patients. Furthermore, according to Beurskens, de Vet, Koke, Van der Heijden, and Knipschild (Beurskens et al., 1995), the numeric response available for the patients from 0 to 100 is also not easy for the patient to inform through the tests of Aberdeen Low Back Pain Scale due to the occurrence of any minor change. Therefore, if there were any more responses available for the patients with chronic low back pain to respond would be effective (Beurskens et al., 1995).
It has been identified in previous researches that the Aberdeen Low Back Pain Scale possesses the weakness of natural variation in large amount (De-Vet et al., 2001). The reason behind such weakness of variation is that the patients of chronic low back pain with low baseline values or minor changes may find this questionnaire useful with more categories of responses. However, the Aberdeen Low Back Pain Scale is the instrument related to ADL, which is not useful in assessing the work limitations (Kuijer et al., 2004). However, it has been considered that recovery of patients with chronic low back pain may be assessed more directly by asking the perceptions of patients regarding their recovery. Thus, the use of Aberdeen Low Back Pain Scale may limit the relevance of individual patients but can facilitate the interpretation for their recovery from low back pain (Costa et al., 2008). Additionally, another limitation of Aberdeen Low Back Pain Scale observed is that the consistent feedback using this tool did not provide effective recovery perceptions for the patients of chronic low back pain because for effective results and feedback, Aberdeen Low Back Pain Scale requires long-term feedback from the patients (Burton et al., 2004). Another additional limitation of using Aberdeen Low Back Pain Scale for the patients with chronic low back pain is to use another tool with it for enhancing the results and effective outcome within the short-term framework (Preuper et al., 2007). Best custom term paper writing.
Different studies have identified that the patients with chronic low back pain are not satisfied completely with the results and parameters of the Aberdeen Low Back Pain Scale (Sherman et al., 2004). According to Rosenberg, Genao, and Chen (2008), the reason behind such dissatisfaction is highlighted in the claims given by them regarding the Aberdeen Low Back Pain Scale that the statements did not completely provide the scenario of their health related to the chronic low back pain. Furthermore, some patients with chronic low back pain claims that if these questionnaires and results of Aberdeen Low Back Pain Scale are sent to their workplaces then they will not consider their pain issues because the questionnaire fails to reflect such issues and represents them healthy and well (Rosenberg et al., 2008). It has been identified by Rashiq, Koller, Haykowsky, and Jamieson (2003) that the test of Aberdeen Low Back Pain Scale is highly subjective because it necessarily does not reflect the quality of life of patients suffering from chronic low back pain.
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