Introduction to Preoperative Anxiety and Its Measurement - Dissertation Example

?Running HEAd: Assessing Preoperative Anxiety with various scales Assessing preoperative anxiety Usage and validity of various scales Type here 2/6/2011 Introduction to Preoperative Anxiety and its measurement Successful surgeries require specific conditions involving several somatic and medical variables (Wilson, 1969). Moreover, the psychological condition of the patient plays a vital role in the success of a surgery (Janis, 1958). This is why it is very important to measure and research on preoperative anxiety. Patients are usually quite worried about the success of their surgery, anxious about anesthesia and the pain they would have to bear once the surgery has been done and their concerns make them anxious. The level of their anxiety impacts their surgery making it all the more important to assess it so that it could be adequately addressed (Shafer et al., 1996). Besides, the above mentioned factors, preoperative anxiety also depends on other factors such as demographic and social environment like sex, age, relationship status, education, as well as the disease, severity, probability of failure, expected complications, required stay in the hospital, etc. Other factors include the information required by the patient, method of anesthesia, etc. This information helps in understanding the required amount of anesthesia as patients with high level of preoperative anxiety need more anesthesia (Shafer et al., 1996). Similarly, their stay in the hospital is prolonged if the anxiety levels are high. The visual analogue scales, unspecific questionnaires such as State-Trait-Anxiety-Inventory (STAI), newly developed instruments such as Anxiety Specific to Surgery Questionnaire ASSQ are some of the available methods for assessing preoperative anxiety (Shafer et al., 1996). Analysis of the APAIS Scale APAIS stands for The Amsterdam Preoperative Anxiety and Information Scale developed in 1996 by the Dutch group of Moermann. Procedures, surgeries, bring significant mental stress with them. Surgeries, treatments, make the patients anxious; hence, preoperative anxiety has an impact on the result of the treatment. The APAIS scale is helpful in evaluating the severity of preoperative anxiety. It is a measure of anxiety and the information needed by the patients. It is a questionnaire consisting of six items and is an economical instrument. A five point Likert Scale is used to rate the items. The rating begins from ‘not at all’ and the fifth being ‘extremely’ (Moermann et. al, 1996). The items 1, 2, 4, & 5 on the scale represent measures of anxiety whereas items 3 & 6 represent need for information. An indicator of the scale’s validity is its correlation measures with the State Anxiety Scale (STAI) which is R=74% (Moermann et. al, 1996), R=67% (Nishimori et. al, 2002), R = 64% (Boker, Brownell, & Donen, 2002). Moreover, another characteristic of APAIS scale is its ability to predict pain after operative procedures have been performed, however, it would not be able to predict the nausea one feels after an operation or vomiting. The following are the items on the scale: 1. “I am worried about the anesthetic. 2. The anesthetic is on my mind continually. 3. I would like to know as much as possible about the anesthetic. 4. I am worried about the procedure. 5. The procedure is on my mind continually. 6. I would like to know as much as possible about the procedure.” (Moerman et. al, 1996) Several analyses were performed to assess the validity of the scale. The assessment evaluated both content and criterion validity. For the assessment of the construct validity, factor analyses was performed whereas concurrent validity was measured by determining the correlation of the APAIS scale with the STAI (Moerman et. al, 1996). Factor analysis measured content validity and it revealed the relationship between anxiety and the need for information. Hypothesis regarding different classes of patients such as sex, experience of surgery or similar operative procedures, were developed and tested against the scale and it was found that the scale was able to satisfy all the hypotheses formed. Moreover, the scale explains the two factors anxiety and need for information up to a 72% (Moerman et. al, 1996). Analysis of DAS24 Every single person in this world cares about his appearance and would be devastated if the appearance gets disordered due to some reason. The outer image of a person is as important as his internal image (Rumsey, Clarke & Musa, 2002). Having to spend the rest of one’s life with an altered appearance could have a significant impact on a person. Altered appearance could result in anxiety, social exile, and impact on the quality of life itself (Rumsey, Clarke & Musa, 2002). However, it is not necessary that every patient who has gone through procedures that alter their physical appearance would respond in the way mentioned above, some might adapt well to the changes (Rumsey, 2002; Partridge, 1990). Several factors such as cultural, social, environmental, and psychological aspects have a profound impact on the behaviors (Endriga & Kapp-Simon, 1999). Moreover, besides the above mentioned factors, the form of the change would also have an impact. For example, it is expected that a person with scars all over his appearance would obviously have more difficulty in coping with the change than the person with lesser scars. The reason behind this might be that the more evident a disfigurement is on a person’s appearance, the more at psychosocial risk he may feel. He may not be able to fit into the social setup due to his own psychological problems, perceptions; moreover, he may feel dejected, lost, and frustrated all the time (Pruzinsky, 1992). However, it is not always the case that we find a relation between the amount of disfigurement and anxiety as some people might be more anxious than others in spite of lesser disfigurement than others (MacGregor, 1970). DAS stands for the Derriford Appearance Scale 24 which consists of 24 items that assesses the adjustment of a patient to distress and dysfunction relating to the self-consciousness towards appearance. DAS24 is the robust and widely applicable form of the DAS59 scale, which was developed to be able to assess the stress and problems patients faced while having to cope with the problems in appearance. Moreover, another objective was to make the scale acceptable for all sorts of patients, both clinical and non-clinical. DAS59 was reduced to DAS24 by the selection of 25 items from the DAS59 scale on the basis of factor loadings, correlation of item to whole, and factor sampling, as well as their clinical usability, which were later refined to 24 (Carr et al., 2000). This scale was tested on 535 patients having different sorts of appearance problem and they were representative of a population. The procedure that shortened DAS59 used the help of the British Association of Aesthetic Plastic Surgeons (BAAPS), invitations were sent out to UK consultant plastic surgeons working in NHS units to participate in the study. Twenty-five surgeons spread all across England, Wales, and Scotland participated in the study. The results from the tests on the patients revealed that the test-retest reliability was 82% and criterion validity with DAS59 was 88%. Moreover, the content validity was exceptional between the samples of the population and patients depending on their concerns regarding appearances (Carr, Moss, & Harris, 2005). The scale is valid with a correlation of 88% with DAS59 (Carr, Harris, & James, 2000) and internal consistency of 92% (Watson & Friend, 1969). DAS24 is shorter while it has a strong grip on the advantages of the original factorial scale. The high correlation between DAS24 and DAS59 strongly proves this point. Therefore, we can safely say that DAS24 is usable in situations with time constraints and the details are not necessary (Carr, Moss, & Harris, 2005). Analysis of DAS59 The DAS59 scale has been formulated for meeting the objective of assessing the emotional and mental stress and the external and internal pressures one faces when going through disfigurements like dealing with the preferential treatment towards the physically attractive in all social situations right from childhood to adulthood (Berscheid, 1981). Disfigurements put people in situations of social and interpersonal difficulties as well as stigmatization and isolation (Rumsey, 1997). The scale is quite sophisticated in terms of evaluating the changes that follow before and after large operative procedures of facial, bodily/sexual features. It is helpful in finding out the mental stability and condition of the patients of cosmetic and reconstructive plastic surgeries by filtering the aspect of appearance that is most significant for the patient. It also assesses psychological distress and dysfunction (Carr, & Harris, 2001). Moreover, another advantage that the scale offers is the data that it provides that helps in performing a cost/benefit analysis of one treatment against another. The development of scale initially began with the formation of an experimental scale that consisted of 136 items as opposed to the 59 items it now has. The 136 items included data from autobiographical studies and phraseology of the respondents. The initial study comprising of 72 respondents to test the validity of the new scale whereas a longitudinal study was undertaken afterwards consisting of 50 respondents. All of these studies showed that the new scale was valid as the collected data was correlated with previously performed psychological tests and consistency of DAS59 with other tests such as the Beck Depression Inventory and the Eysenck Personality Questionnaire was found to be 98% (Eysenck, & Eysenck, 1991). Afterwards, a large database of 606 plastic surgery patients was used to refine the scale where the number of items were reduced to 59, DAS59. Later, an even shorter form of the scale was introduced known as the DAS24. DAS24 generates a single score as opposed to DAS59 that generates five factorial scores as well as a total score. The 59 items are in the form of statements and questions and the respondent answers them in the Likert format ranging from ‘almost never….almost always’ and ‘not at all distressed….extremely distressed.’ The beginning part gather information regarding the demographics of the respondent and the appearance factor he is most sensitive about. The respondent scores it himself according to given instruction. The higher the score, the more severe the level of stress for the patient. The scale has an extremely high correlation of 99% with the original experimental scale along with other psychological tests like the Social Anxiety and Distress Scale (Watson, & Friend, 1969), the Beck Depression Inventory (Beck, & Steer, 1987), the State and Trait Anxiety Inventory (Speilberger et al., 1983). Hence, we can say that DAS59 could be effectively used for changes in conditions. Analysis of VAS VAS is the short of the Visual Analogue Scale, which is a measure of any subjective phenomenon that could be self-administered. It has application in various field of medicine (Bijur et al., 2001). The scale is extremely usable as it is simple, and could be used frequently and repeatedly while being used on different subjects (McGrath et al., 1996). Technology is taking over in every field, similar is the case with medicine where more and more attention is being given to the collection of patient data with the help of computers. The Visual Analogue Scale has been frequently used to measure the degree of anxiety in patients with anxiety disorders as well as patients with no such disorders. It is extremely successful for measuring anxiety and can sense changes as it has been used on anxiety disorder patients and healthy control subjects and the scale was able to sense the change and the results it gave were in synchronization with the change of subjects and their behavior (Gift, 1989). VAAS comes in two forms, eVAAS, the electronic measure of anxiety and pVAAS, which is its paper version. Both the electronic and paper version are similar. However, in the electronic version scoring is carried out automatically and reported immediately and hence, is error free ( van Duinen, Rickelt, & Griez, 2008). The VAS consists of a 100-mm line with the farthest left indicating minimum or zero anxiety indicating that the patient is not anxious at all and the farthest right indicates the maximum anxiety level indicating highest level of anxiety. Patients while taking this test mark on the line to indicate their level of anxiety (Miller et al., 1995). Following is a sample of the Visual Analogue Scale (Pain rating scales, n.d.): Analysis of STAI STAI or the State Trait Anxiety Inventory is a measure of anxiety. The scale has the ability of differentiating between temporary anxiety also known as ‘state anxiety’ and a long term condition of anxiety known as ‘trait anxiety.’ The conciseness of the scale helps it in implementing it on people with limited understanding or coming from uneducated backgrounds. It is worldwide measure of anxiety. It consists of 20 statements indicating the level of anxiety that the patient maybe facing along with scores from 1-4 indicating the level of emotion for that particular statement (Spielberger, 2010). The construct validity of the scale was found in a study through a measure of correlation between Panic Disorder and right-hemisphere brain through 22 patients who were suffering from Panic Disorders (Smeets et al., 1996). There was a positive correlation between the Anxiety Sensitivity Index and the STAI-trait and STAI-state. 29 male undergraduate students were used for finding the test-retest reliability under high stress social situations. The correlations of state anxiety and trait anxiety was found to be 40% and 86% respectively (Peterson & Reiss, 1987), which are similar to the correlation found under test situation (Tilton, 2008). Analysis of HADS The hospital anxiety and depression scale came into being as a result of a study that was undertaken at a general medical hospital outpatient clinic (Zigmond, & Snaith, 1983). Patients were asked to fill a questionnaire that had questions related to anxiety as a whole or depression. Moreover, while making the questionnaires, translations to other languages was also kept in mind. Later, once the patients had filled in the questionnaires, personal interviews with them were also conducted and this exercise helped in reducing the number of questions in the questionnaire. It takes 2 to 5 minutes to complete the test (Snaith, 2003). Patients choose from one of the four responses given at the end of each questions related to anxiety or depression. Those questions that are related to anxiety are marked ‘A’ whereas those related to depression are marked ‘D.’ Moreover, the score of each option is given at the right side of the column with each option (HADS, n.d.). A review of 747 papers that had used HADS were reviewed to find the validity of the scale (Spinhoven et al., 1997). A factor analysis in the study revealed that HADS gave a two factor solution for Anxiety (HADS-A) and Depression (HADS-D) with correlations between the two varying from 40% to 74% with a mean correlation of 56%. Similarly, judging HADS on sensitivity and specificity through specific case analysis using three studies that compared it to the General Health Questionnaire, it was found to be 80% showing high sensitivity and specificity of the scale, which is very similar to the specificity and sensitivity of the General Health Questionnaire (GHQ). This is specifically significant considering that HADS is particularly shorter than GHQ. The correlation of other similar assessment methods and techniques and HADS ranged from 49% to 83% (Bjelland et al., 2001). Hence, we can safely say that HADS can serve as an excellent technique for evaluating the level of anxiety and depression in a patient coming from various backgrounds. Moreover, a self report instrument can be considered reliable if the alpha of Cronbach’s coefficient is 60% (Nunnally, & Bernstein, 1994), which was fulfilled by HADS in all the studies proving to be an extremely reliable reporting instrument (Bjelland et al., 2001). Analysis of MAACL Multiple Affect Adjective Check list (MAACL) came into being as a result of an extension of the Affect Adjective Check list (AACL) upgrading it to a multi-scale method. It is extensively used to study changes that result from behavioral, cognitive, and dynamic therapies. It is a widely used assessment technique for measuring stress in situations resulting from hurting of egos, frustration, failures, evaluations, deprivation, threat of pain, extensive mental and physical exercise and training, surgeries, pregnancy, and several more (Zuckerman, & Lublu, 1965). The technique consists of five basic scales anxiety, depression, hostility, positive effect, and sensation seeking which are composed together to form two composite scales Dysphoria comprising of Anxiety, Depression, and Hostility whereas the other scale comprises of Positive affect and sensation seeking forming PASS (MAACL-R, 2010). The Profile of Mood States is a model that assesses the mood profiles of respondents. POMS consists of 65 items that respondents rate on a 5-point scale starting from 0 to 4 (McNair, Lorr, & Droppleman, 1971). It was used to compare with MAACL and find its concurrent validity. The state form of MAACL had a high correlation with POMS scale except H. Similarly, the trait correlations were also similar to state correlations. Internal consistency and test-retest reliability was also high along with the overall validity of the scale (Lubin, Denman, & Van Whitlock, 1998). Analysis of LAAS LAAS stands for Linear Analogue Anxiety Scale. It is a method of assessing anxiety in patients. It is similar to the Visual Analogue scale. The patients indicate their level of anxiety on a 100mm horizontal scale ranging between the limits of ‘calm’ to ‘terrified’ depending on their level of tension at the particular moment. A study was conducted to compare the scale with other validated scales MAACL and HAD. Hundred consecutive day care patients going through termination of pregnancy were asked to fill in a questionnaire consisting of the HADS, MAACL and LAAS tests. However, 84 patients were able to fill the LAAS part of the questionnaire. Data symmetry was measured by the Pearson's coefficient of skewness. A zero value indicates that the data is symmetrical, and negative value indicates that data is skewed to the left whereas positive value indicates data is skewed to the right. A normal distribution has zero kurtosis whereas a negative value indicates a platykurtic or flat distribution and a positive value indicates peaked or leptokurtic distribution. The LAAS scores were all skewed to the right showing a peaked distribution and a platykurtic distribution. There was a high degree of correlation between LAAS and MAACL scale up to a 67% (Hicks, & Jenkins, 1988). Analysis of NRS Numerical Rating Scale is a method of assessing preoperative anxiety in numerical form. The method of assessing through NRS is that patients fill in a questionnaires with specific questions and they assign numbers ranging from 1-10 based on their degree of calmness where 1 means minimum level of anxiety and 10 indicates maximum anxiety level. The methodology adopted for assessing preoperative anxiety is with the help of a scale. The patients are asked to rate their pain or anxiety on a scale with the highest being 10. The scale asks questions such as ‘what number would you give to your pain right now?’ or ‘At what number is the pain acceptable for you?’ The validity and reliability of NRS has been tested on Swedish population without an inclusion of zero anxiety. Following is an example of a test that is given to the patients: (Pain rating scales, n.d.). Analysis of NVAAS The numerical Visual Analogue Anxiety Scale is yet another measures for assessing preoperative anxiety in patients. Moreover, it may also be helpful in finding a link between the preoperative anxiety and the pain one feels after surgery has been completed. The patients are asked to rate their anxiety level on a 100mm numeric anxiety scale with ‘no anxiety’ at one end with a 0 rating given to it and ‘anxiety as bad as you can imagine’ with the rating of 10 given to it. It is concise and fairly easy to use as the patients can easily rate their level according to the anxiety they may be experiencing at that particular time. The validity and reliability of the scale was found with the help of a study on 36 patients going through a colorectal surgery who were asked to rate their anxiety level on NVAAS and the State-Trait Anxiety Scale (Elkins et al., 2004). The correlation between the two scales was quite high at 64% and probability of error being less than .0001. Moreover, the NVAAS showed significant correlation with the pre-surgery anxiety scale rating of STAI with 46% and post-surgery anxiety rating of VAS and 35%. Hence, we can say that it is a sensitive measure of anxiety and it has the tremendous advantage of being extremely short and easy to use making it more usable than any other scale (Elkins et al., 2004). Analysis of YPAS Zeev Kain along with his other colleagues at the Yale University of Medicine worked very hard to develop and validate a scale that is suitable to the assessment of preoperative anxiety of children who are too young and hence, are unable to perform other self-report assessments (Kain et al., 1997). YPAS stands for the Yale Preoperative Anxiety Scale and it started off from Child Neuropsychology and had 21 situations, all various forms of anxiety. On the basis of several video tapes of children just before anesthesia is given to them and aged between 2-6, 5 major domains of anxiety were developed. The validity of the scale was tested by a comparison with the ‘gold standard’, which is the STAIC on which over 1000 studies have been completed (Kain et al., 1997). Scores of YPAS were compared with those of STAIC and it was found that YPAS had significant concurrent validity. Similarly, it was also found that the YPAS was able to depict changes in conditions with the help of changing levels of anxiety, for example, there was a significant rise in stress from the level of stress in the holding area to the level of stress in the operating room with the mask. The rise in level indicates the YPAS is functioning according to the level of anxiety and is a perfect measure of anxiety. YPAS was able to pass the tests as only five patients out of the whole lot were found to be misclassified while using STAIC as a threshold (Kain et al., 1997). Comparison of HAD, MAACL, and LAAS In order to perform a comparison of HAD, MAACL, and LAAS a test was conducted on 100 consecutive day case patients who were undergoing termination of pregnancy who were asked to fill in a questionnaire that had three sections (Hicks, & Jenkins, 1988). The first section of the questionnaire was the HAD Scale comprising of 7 multiple choice questions with 4 options. Patients ticked the option that was closest to their situation. The higher scoring indicated higher levels of anxiety. The second part of the test included the MAACL that had a multiple affect adjective check list consisting of 21 adjectives. The positive sign indicated ‘anxiety present’ while the negative sign indicated anxiety absent. The patients were supposed to tick those adjectives that were closest to their feeling. The last part of the questionnaire was the LAAS with the minimum ranging from ‘calm’ to ‘terrified.’ The study found that there was a high degree of correlation between HAD scale and both MAACL scale and LAAS scale with the correlation coefficient of 74% and 67% respectively (Hicks, & Jenkins, 1988). Another factor indicating ease of use of each of the scales was the fact that all 100 patients in the study were able to complete the HAD scale and the MAACL scale showing that they are easier to understand and interpret whereas 84 patients were able to complete the LAAS scale. The distribution of the HAD scale was the closest to the normal distribution with almost zero kurtosis (Hicks, & Jenkins, 1988). Comparison of HAD with VAS and STAI In order to compare the HAD, VAS, and STAI scales for measuring preoperative anxiety, 44 patients awaiting breast cancer surgery were used in the study. Each patient complete the HAD, STAI, and VAS. The HAD test included 14 statements with the 7 of them related to anxiety. The patients scored their responses from 0-3 with 0 being the minimum. The STAI test comprised of 20 statements indicating levels of anxiety with four descriptors each describing a certain anxiety level. Similarly, the VAS consisted of a 100-mm line with the left side indicating minimum anxiety. The conclusions found from the study were that the correlation between HAD and STAI was 81% while that between STAI and VAS was 62% (Miller et al., 1995). The three scales showed greater agreement with each other when judged using normative cut-off values. Therefore, we can safely say that the three scales are somewhat equivalent in assessing preoperative anxiety in the present of normative data and hence, can be interchangeably used for assessing anxiety depending on the state of the patient (Miller et al., 1995). References Moerman N, van Dam FS, Muller MJ, & Oosting H (1996). The Amsterdam Preoperative Anxiety and Information Scale (APAIS). Anesth Analg. 82:445-51. Nishimori M, Moerman N, Fukuhara S, van Dam FS, Muller MJ, Hanaoka K, Yamada Y (2002). Translation and validation of the Amsterdam preoperative anxiety and information scale (APAIS) for use in Japan. Qual Life Res. 11:361-4. 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