Measuring tools Essays

Measuring tools Essays Measuring tools Essay Measuring tools Essay Either the aim or objective and the type of quantitative approach was clearly stated within the abstract or summary of all the papers. Identification of the purpose and type of research at the beginning of the paper has several immediate advantages and limitations. From a nursing perspective, it is possible to determine if the research is relevant to patients in a particular care setting. However, as McCaughan (1999) points out, subtle differences may only be apparent with further exploration of the study. Secondly, clarity of purpose suggests a well-planned study that will deliver valid and useful data. Thompson (1999) concurs with this view and suggests that without a clear statement of aims the reader is unable to determine whether the research achieves its objectives or not. Furthermore, with unclear aims, there could be a tendency towards data-trawling, which may result in providing spurious results. Although I agree with the views of Thompson (1999) and McCaughan (1999), I believe there can be concerns with stating the type of method used in conducting the research. For instance, there could be a tendency to accept the design at face value or for it to bias the critical analysis of the study. Lais (1998), study is described as a prospective, nonrandomised study. According to Woods and Catanzario (1988), a prospective design aims to observe a sample on at least two occasions over a period of time, the aim being to reduce the likelihood of bias in reporting the relationship between the cause and effect. Whereas Lais (1998) study consisted of gathering information for a period of one month and could therefore be called prospective, it is not clear whether all the criteria for a true prospective design were applied or not. However, this is not to say that the research findings themselves would not be valid and reliable. Rather that even though there is a clear statement of the type of research, care must be taken that it does not influence personal judgement or the analysis of the study. Having determined that initially, the information given in the abstract of a study can have advantages and limitations, the next point will briefly consider the value of including or excluding a literature review within the study. LITERATURE REVIEW None of the studies reviewed in this assignment contained a literature review. However, there is some evidence that previous studies had been used to inform the investigations. Homer (1998) refers to previous studies within the methodology section and again in the discussion. The studies referred to are included in the reference list. Although the material in the reference list is relevant to the topic it only contains references for seven previous studies. Similarly, Lai (1998) cites previous studies within the discussion. Again the reference list only contains a few references. On the other hand, Curran et als (2000) study incorporates references to numerous previous work throughout the text. The value of including a literature review in a quantitative study is that it enables the research problem to be put into context or to identify gaps and weaknesses in prior studies so as to justify the current investigation. Also as Carnwell and Daly (2001) discuss it is valuable in demonstrating insight into the current state of knowledge within the relevant field. However, the exclusion of a literature review does not necessarily mean that the researchers did not undertake one. On the other hand, exclusion makes it difficult to determine the reason for undertaking the studies. For example, although, it appears that Lais (1998) study may have been carried out, at least in part, to support a cost saving initiative within his medical centre, none of the referenced material concerns this issue.  However, there is a common understanding throughout the studies regarding the nature of the topic being investigated. In particular, all of the papers acknowledge that peripheral venous cannulae are associated with the development of phlebitis. THEORETICAL/CONCEPTUAL FRAMEWORK Although none of papers (Curran et al 2000, Homer 1998, Lai 1998) identify a theoretical or conceptual framework that guided the research, there is allusion to the principles of some of the theories. For example, Curran (2000) discusses two causes of phlebitis, insertion site infection and physiochemical reactions. Similarly, Lai (1998) refers to infusion-related phlebitis and sepsis. On the other hand, Homer does not appear to refer to any theoretical framework in his study. In conclusion, it does not seem that theoretical models had a major influence on the studies. DEFINITIONS OF PHLEBITIS The studies have all identified phlebitis by using clinical indicators and severity rating scales. However, there does not appear to be common indicators or scales to identify the severity of phlebitis. For example, Lai (1998) has defined phlebitis as a palpable cord or at least two of the following, tenderness, warmth, erythema and induration. There is no particular reference as to the origin of the definition, although it appears to have been adapted from the inflammation scale used by the IV team within the hospital where the study took place. Similarly, the origin of the inflammation scale is not reported. According to Lais (1998) definition, phlebitis would be given a score of 3 or 4. Homer (1998) also defines phlebitis by clinical categorisation and allocating scores. However, the categories and scoring are different to those used by Lai (1998). Using Homers (1998) definition would give phlebitis a score between 2 and 4. Homers (1998) scale is not referenced but a significant difference from the one used by Lai (1998) is the exclusion of induration as a clinical indicator. Curran et al (2000) referred to the existing literature for indications of phlebitis. The eventual approach adopted contained two categories, erythema equal to or extending more than 3cm from the insertion site and/or purulent discharge with either or both being given a rating of 2 if present. Curran (2000) reports that this scale had been used in previous studies and includes references within the text, but does not offer any further information. However, there is no discussion as to any previous validation process that may have been used. As we have seen, phlebitis has been categorised and classified in different ways by different authors unique to their own study. Previous studies may have guided some of the categorisation. For example, Homer (1998) refers to the classification of phlebitis by Maki and Ringer (1991 cited in Homer 1998 p5) and Tager(1983 cited in Homer 1998 p5) but develops his own scale for classifying phlebitis. As a result, there appears to be no consensus of opinion regarding the rating and definition of phlebitis between the studies under review.  As well as impacting on the accuracy of assessing and identifying severity of phlebitis, the lack of a common assessment tool for defining and measuring phlebitis may impact on the generalisability of the research. Campbell (1998) suggests that the use of a uniform scale that measures the degree of phlebitis is also beneficial in providing criteria for standardising documentation. ACCURACY, VALIDITY AND RELIABILITY OF THE ASSESSMENT TOOL Each of the studies used clinical indicators and a rating scale to determine and measure the severity of phlebitis. The strength and appropriateness of this type of measuring tool has been demonstrated in other quantitative studies within the same field. (Dinley 1976, Maddox and Rush 1977, Baxter Healthcare Ltd. 1988 cited in Campbell 1998 p 1311) However, there are limitations and weaknesses with the tools used in the studies under review. None of the researchers have discussed how validity and reliability was assessed. Although both Lai (1998) and Homer (1998) have used tools that do not appear to have been used in previous situations, there is no report on a pilot study being carried out prior to the main study. Lais (1998) measurement tool has a number of limitations. Within the study Lai (1998) reports that the intravenous site was monitored according to a well-defined inflammation scale and has published the indicators and rating for the inflammation scale in the study. However, the tool that Lai used to obtain the data on phlebitis in his study was not the reported inflammation scale. Lai (1998) appears to have used elements of the inflammation scale and designed a scale that has some differences from the inflammation scale that he reported was used. The inflammation scale uses pain and swelling as clinical indicators but in the scale that was used in the study swelling has been excluded and pain has reduced to tenderness. Another point of concern is the implication that the severity of phlebitis could be measured on a scale designed to measure the presence and severity of inflammation. This may lead to confusion between rating phlebitis and inflammation. In other words, it is not certain that the tool actually used measured what it was supposed to measure. Homer (1998) referred to other studies before adopting a different set of clinical indicators in his scale that he reports as being more rigorous than Maki and Ringers (1991 cited in Homer 1998 p5) scale but less so than Tagers (1983 cited in Homer 1998 p5). However, there does not appear to be any reference to testing validity of the scale. A point of accuracy concerns the use of the scale for measuring infiltration as well as phlebitis. Although, the measuring of infiltration is not mentioned in the discussion section, the methods section gives the grading of infiltration as 1-3. The grading on the scale for phlebitis is 2-4. According to Homer (1998), the majority of the incidences of phlebitis were graded at 2. Consequently, phlebitis and infiltration were both graded as 2 using the same clinical indicators. Again, this raises the point of whether the scale measured what it was supposed to measure. The strength of Curran et als (2000) measurement tool lies in the fact that it had been used in other studies. However, there is no discussion as to the validity or reliability of the tool. It is also unclear as to whether Curran et al (2000) carried out a pilot study or not. There is a reference in the paper to collecting data on forty catheters, which is not the total number of the whole data collection. However, although analysis was carried out on the data collected from this, there is no further discussion. In summary, there appears to be serious weakness and limitations with the accuracy of the measuring tools. Validity and reliability appear not to have been tested. As McCaughan (1999) points out, if measuring tools are not valid then neither are study findings. Error due to the measuring technique used, the instrument itself or the person doing the measuring may affect reliability. Therefore, the next point will consider the issue of interrater reliability.