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Patient satisfaction with anesthesia services

Sylvie Le May, RN MSc^*,, Jean-François Hardy, MD, Marie-Christine Taillefer, BSc and Gilles Dupuis, PhD

From the Department of Anesthesiology,
^* Faculty of Medicine and the Faculty of Nursing, University of Montreal, and the
Department of Psychology, Université du Québec à Montréal, Montreal, Canada.

Address correspondence to: Dr Jean-François Hardy, Department of Anesthesiology, Faculty of Medicine, University of Montreal, C.P. 6128, succursale Centre-Ville, Montreal, Quebec, H3C 3J7, Canada. E-mail: jean-francois.hardy{at}umontreal.ca

	Abstract

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Purpose: The evaluation of services by patients is an essential component of continuous quality improvement in anesthesiology. Little is known, however, about how to achieve this objective. Our goal was to conduct a systematic review of all available studies on patient satisfaction with anesthesia services, thereby ascertaining the present level of knowledge in this field and suggesting ways of improving current measurement methodologies.

Source: We reviewed relevant major data banks - Medline, Dissertation Abstract, Psyclit and Cochrane - between 1980 and 2000 and bibliographies from primary sources. We used the following keywords for our search: quality improvement, anesthesia, quality, patient perceptions, consumer satisfaction, continuous quality improvement, outcome measures.

Principal findings: The review yielded 14 pertinent studies. Studies were divided into two groups (A & B), according to the quality of the psychometric evaluation (tests performed to verify the reliability and validity of an instrument). While all studies reported high levels of patient satisfaction with anesthesia services, many used methods of questionable value. None of the 14 studies controlled for any confounding variables, such as social desirability. Four studies had seriously biased their data collection and the majority of the studies lacked rigour in the development of the instrument used to measure patient satisfaction. Only one study presented a definition of the concept measured, and none provided a conceptual model of patients' satisfaction with anesthesia services.

Conclusion: The currently available studies of patient satisfaction are of questionable value. Only rigorous methods and reliable instruments will yield valid and clinically relevant findings of this important issue in anesthesiology.

THE major data banks contain a vast array of articles, published between 1980 and 2000, that examined patient satisfaction with medical care. Few of these publications, however, cover patient satisfaction with services provided by anesthesiologists. Despite the paucity of publications in the field, several authors believe that patient satisfaction is an attribute of the quality of care in anesthesia.^1–3

Recently, a review on patient satisfaction and anesthesia care was published,⁴ focusing on the appropriateness of different methodologies used to measure patient satisfaction. In contrast, this present article seeks to provide a more critical review of the methodology, the development of the instrument used by the authors and psychometrics (when available) and the results obtained by selective studies treating this concept.

	Sources

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Our methods were inspired by Cook.⁵ Her suggested format for a systematic review of the literature includes: a description of the data sources, study selection, data extraction-synthesis and a presentation of the results.

Data sources
We searched Medline, Current Contents, the Cochrane Data Base, and Dissertation Abstract for studies published between 1980 and March 2000. We searched the bibliographies of primary and review articles for other relevant studies. Our search was restricted to French and English publications.

We used the following key words to retrieve articles: quality improvement, anesthesia (including anaesthesia), quality, patient satisfaction, patient perceptions, consumer satisfaction, continuous quality improvement, outcome measures. We also combined some of the main keywords: quality and anesthesia, quality improvement and anesthesia, patient (and consumer) satisfaction and anesthesia, quality and patient satisfaction and anesthesia (including anaesthesia).

Study selection
We selected studies that emphasized patients' satisfaction with anesthesia services. Included were studies covering both ambulatory and hospitalized patients. Since relatively few studies focused mainly on patient satisfaction with anesthesia services, we did not use any selection criteria and included all publications in the present review. We excluded drug trials regarding patient satisfaction over pain management. These studies used relief of pain as the sole indicator of patient satisfaction.

Data extraction and synthesis
Data were extracted following three specific categories: source, population (characteristics of the sample), a summary of the main results vis-a-vis patient satisfaction and the instrument used. Studies were divided in two groups (A and B). Group A includes those studies in which no psychometric testing (tests performed to evaluate the reliability and validity of instruments) was done on the scales employed to measure patient satisfaction. Group B includes the studies that performed certain psychometric tests on the scale employed to measure patient satisfaction.

	Principal findings

TOP Abstract Sources Principal findings Discussion Conclusions References

 
We found 14 studies that focused on patient satisfaction with anesthesia services. A synthesis of the data extracted from these studies is presented in the Table. Studies were divided in two groups (A & B) according to the quality of the psychometric evaluation (tests performed to verify the reliability and validity of an instrument) of the instrument used to collect data. Group A includes studies where the authors did not perform any psychometric tests on the instrument they used. Group B includes the studies where the authors performed some psychometric tests on the instrument they employed.

Main results on patient satisfaction and psychometrics
The majority of studies, whether from group A or B, reported high levels of patient satisfaction with anesthesia. However, when patients were given an opportunity to express themselves freely, they noted certain unsatisfactory elements in the care received from anesthesiologists.

The Group B studies, although using more rigorous methods than those in Group A, still obtained very high levels of satisfaction. Only one study¹¹ (in Group B) defined patient satisfaction, and none of the six studies included a conceptual framework of their constructs. Furthermore, no study included other questionnaires to control for confounding variables, such as level of psychological distress or social desirability, even though these variables may affect a patient's ability to properly complete a questionnaire on satisfaction and to answer rationally.

The psychometric testing of the scales was performed in a variety of ways. Shevde & Panagopoulos,¹⁹ presented a factor analysis of the data to reveal the presence of four distinct factors (specific complications of anesthesia, characteristics of the anesthesiologist, anxiety about being hospitalized and pain). No other testing was performed on their scale. Pestey¹⁶ evaluated the reliability of her scale using a test-retest with short term surgery patients only (n=38). Pearson correlation coefficients were calculated for each individualized questions (Q2=0.76, Q3=0.88, Q4=0.76, Q5=0.79, Q7=0.66). Whitty et al.,¹⁵ developed a scale using patient focus groups, comments from anesthesiologists and a theory of patient satisfaction. Content validity was verified with patients, anesthesiologists, experts on questionnaire design, and a "fog index" (Microsoft Word software that screens a text and identifies words exceeding the level of grade 6). No other testing was performed on their scale. Tong et al.¹¹ used a Kappa (interrater agreement) between nurses and anesthesiologists to assess the reliability of their two scales (a standardized check-off form for adverse events, a 24-hr postoperative telephone questionnaire). Values of k >0.9 were obtained for both scales. As to the reliability of the questions on satisfaction, these authors relied on the psychometric informations obtained in a previous study²⁰ and did no testing of the data (data obtained using the questionnaire of Abramovitz and colleagues). Dexter and colleagues¹³ performed various tests on their new scale (Iowa Satisfaction with Anesthesia Scale [ISAS]) and obtained a value of 0.80 for internal consistency (Cronbach's Alpha), and correlations of R² = 0.74 (after one hour) and R² = 0.76 (after four days) for stability (test-retest). Content validity (evaluation of the extent to which the method of measurement includes all the major elements relevant to the construct being measured) of the ISAS was verified once, before the study began; the verification was performed by professionals. To establish convergent validity, the authors compared patients' overall scores to those predicted by their anesthesia provider (R² = 0.23, P > 0.01). Fleisher et al.⁹ relied on the correlation between the question regarding quality of care and the one regarding satisfaction with pain management to verify the internal consistency of their instrument. A Cronbach's Alpha of 0.62 was obtained. No other testing was performed on the scale.

	Discussion

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Overall, surveys of patient satisfaction presented in this review yielded very positive results. Unfortunately, these results are often accepted at face value and considered as the sole indicator that the services offered by the department of anesthesiology, as evaluated by patients, are adequate. Since the results are so favourable, the incentive to improve further the quality of services provided is slight.¹¹ Only one author¹⁰questioned the high level of satisfaction suggested by their results: "This apparent satisfaction should therefore give the anaesthetist little cause for self-congratulation, since it implies that the patient neither expects nor demands a high standard of service or expertise from his anaesthetist...".

Another possible explanation for these positive results is that most researchers have a bias towards measuring satisfaction. In other words, they do not allow elements of dissatisfaction to emerge from their surveys. Questionnaires are oriented more towards the researchers' desire for positive results. They do not offer open-ended questions where patients can advance opinions or express dissatisfaction concerning elements covered or not by the survey.

Only one study¹¹ presented a clear definition of the concept of patient satisfaction. As for the remainder, since no definition was provided, it is not clear what these studies truly measured. For example, the ISAS scale¹³ appears to measure more patients' physical condition at a precise moment in time than the patients'satisfaction regarding anesthesia services. Further, none of the 14 studies presented a conceptual framework relative to patients' satisfaction with anesthesia services, thus leaving the reader in the dark as to what variables might explain the underlying concept.

Another important cause for concern is that no study attempted to control for any confounding variables. Respondents might not be answering the items of primary interest for the reasons we assume. There may be other motivations influencing their responses. One type of motivation that can be assessed fairly easily is social desirability. Social desirability is defined as the motivation of a person to present herself or himself in a way that society regards as positive.²¹ If respondents are influenced by social desirability, they may distort their answers and thus invalidate their evaluation of satisfaction. For instance, in the Dexter et al. study,¹³ 90% of the respondents, in the first version of their instrument, answered that they totally agreed with the statement "I like my anesthetist". Also, in the study by Keep et al.¹⁰ one patient who had been awake during her esophagoscopy mentioned that she was satisfied with the anesthetic but would prefer to be asleep the next time! Did social desirability influence or help to explain the high levels of satisfaction obtained? Since none of the 14 studies reviewed controlled for social desirability, the validity of the results remains open to question. Perhaps the use of Marlow & Crowne's abridged social desirability scale,²² along with a patient satisfaction scale, would help to increase the validity of the results obtained by excluding respondents vulnerable to social desirability.

In at least four of the studies reviewed,^7,8,13,17 patients may have been influenced by either the presence of the anesthesiologist or the suspicion that the anesthesiologist could identify them. For instance, if the anesthesiologist remains nearby while the patient is completing the questionnaire, as occurred in three studies^10,13,17 the patients' right to anonymity and confidentiality is not protected. Patients cannot be expected to express their comments, suggestions or grievances if they have even the slightest doubt that their right to confidentiality and anonymity is not being respected.²³

Few clinicians are aware of the importance of psychometric evaluation in the development of a new scale.⁴ For example, Dexter et al.¹³ tested for reliability after an interval of four days, mentioning that "the test-retest method of assessing reliability is sensitive to the time interval between testing. The longer the time interval, the lower is the reliability". Yet, for paper-and-pencil measures, experts recommend a waiting period of two weeks to a month between tests, the goal being to keep subjects from remembering their answers to the first test, which could lead to an overestimation of the test's reliability.^21,24 Further, it is considered irrelevant to perform test-retest evaluation with instruments measuring patient satisfaction since this concept may vary in time and it is also influenced by the effect of memory which is an undesirable consequence in the measurement of this concept. It is more appropriate to focus on obtaining reliable results regarding the internal consistency of the scale, thus an elevated Alpha of Cronbach. Similarly, having a small developmental sample (less than 10 subjects per items) to evaluate internal consistency (Cronbach's Alpha) can produce inappropriately favourable results.^21,25 When the ratio of subjects to items is relatively low and the sample size is small, correlations between items will be influenced by chance to a substantial degree. An Alpha of Cronbach of 0.80 using only 49 subjects, on a scale of 11 items,¹³ should therefore be questioned. Finally, even the employment of a very large sample¹² (10,811 patients) did not compensate the evidence and consequences of a lack of rigour in the methods and the development of the instrument to measure patient satisfaction. Indeed, in the study by Myles et al.,¹² the variable «patient satisfaction», considered as a major outcome, was measured by a question with only three choices of answer and results dichotomized between satisfied vs somewhat dissatisfied-dissatisfied. Such strategy is not very well considered,²⁶ and it does not generate enough variance in the distribution of the data collected. In addition, services offered by anesthesiologists include many components. We doubt that such a complex issue can be properly evaluated by only one question. Thus there are serious doubts about the significance of results obtained with an unvalid and unreliable instrument. Further, even though the authors recognize the influence of social desirability on respondents, no measures were taken to evaluate the impact of this important confounding variable.²⁷

The process that must be followed to obtain valid results is complex. It involves more than writing up a few questions and passing them along to the desired population. As well, a newly developed scale must be tested to verify what it really measures, in view of producing valid results. The initial testing of a scale is not sufficient to verify all of the attributes of both reliability and validity of the scale. Results obtained with a new scale must therefore be interpreted with caution. For the sake of psychometrics, one must "sacrifice" at least one sample; only then can one pretend to significant results on the concept measured.²⁶

In a first trial, such psychometric measures as establishing content validity, internal consistency and construct validity (determines whether the instrument actually measures the theoretical construct it purports to measure) are considered sufficient for evaluating the properties of a scale, taking into account that a theoretical construct of the variables of the study is presented at first.²⁶ Indeed, it is inappropriate to try to perform every psychometric test available on a new scale in a single study. Achieving the complete psychometric profile of a new scale takes time.²⁶ Any new instrument must go through several specific phases and trim before it can be considered to be reliable and valid. Also, the control of major confounding variables is essential to reduce the "contamination" of the main variable (e.g. satisfaction) to be measured by an instrument.

The task of maintaining reliability and validity of instruments is never concluded. Measurement devices are nearly always subject to the effects of social context. Values and practice patterns change, individuals think differently about a number of matters, and terminologies go out of fashion.²⁸ Scale development is a continuous and retroactive process. Finally, care should be taken when attempting to generalize results obtained with a new instrument of unestablished validity and reliability; otherwise, one risks making false assumptions concerning the population from which the sample was drawn.

	Conclusions

TOP Abstract Sources Principal findings Discussion Conclusions References

 
The perceptions of patients, along with quality assurance, are an important component of the evaluation of the quality of services in anesthesiology. Even though perceptions are subjective, this information is important to anesthesiologists. Indeed, patients offer an unique perspective for evaluating the nontechnical aspects of medical care.²⁹ However, to be useful and valid for clinicians and researchers and to engender improvement in the practice of anesthesiology, such information must be collected using rigorous methods and a valid, reliable instrument derived from a conceptual framework. It is doubtful that the results of the studies presented in this review truly represent perceptions of patients regarding the anesthesia care received.

As with all standardized data collection, creating and performing high quality surveys of patients' perceptions can be challenging. Valid and reliable patient survey data can enable practitioners to identify areas for improvement, and demonstrate to external reviewers the quality of care they provide to their patients.²⁹ That is why the development of valid and reliable instruments to measure patient satisfaction must adhere to specific psychometric requirements and control for major confounding variables. The procedure is complex. Use of a non-validated and/or non-specific instrument will only produce unreliable and meaningless results. Generalization of results from a given patient population is hazardous, especially when the initial methods are questionable.

Finally, this review allowed emphasis on the absence of appropriate instruments to measure patient satisfaction with anesthesia services, the many biases present in the methodology employed, the lack of rigour regarding the psychometric testing of the instrument used and also the very high levels of satisfaction usually obtained by surveys on patient satisfaction with anesthesia services to be demistifyed. We proposed solutions to increase the validity of the measurement of patients' satisfaction regarding the services provided by anesthesiologists.

	Acknowledgments

 
The authors would like to acknowledge the outstanding secretarial support of Mrs. Diane Charbonneau, Nicole Charbonneau and Céline Charbonneau from Accès Secrétariat, Blainville (Qc). We are also grateful to Mrs. Wendy Dayton, specialist in medical redaction, for a thorough review of an earlier draft of this manuscript.

	Footnotes

 
This review was supported in part by the Department of Anesthesiology, Montreal Heart Institute, Montreal, Canada and by the Alma Mater Fund of the Faculty of Nursing of the University of Montreal, Montreal, Canada.

Accepted for publication October 22, 2000.

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