A measure called the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (UUIACS) was developed and its validity and reliability were examined. The 49 questions that comprised the original draft of the UUIACS were created based on interview data. Based on data from 172 participants, exploratory and confirmatory factor analyses were conducted. As a result of exploratory factor analysis, the UUIACS e retained 17 items and extracted four factors (“Lack of decision-making cues”, “Lack of information and complexity of information interpretation”, “The ambiguous nature of the disease”, and “The unpredictable living with UIA”). All of the UUIACS items showed adequate internal consistency. Between the UUIAC scale and the Universal Uncertainty in Illness Scale (UUIS), the Health Locus of Control (HLC) scale, and the SF-36v2 ® (Japanese version), positive correlations were found between the UUIACS and UUIS, and the HLC scale at a 1% significance level indicating concurrent validity. According to confirmatory factor analysis, the UUIACS had an acceptable goodness of fit. Given these findings, the UUIACS was judged to have satisfied the criteria for use in a clinical setting, although further investigation was required.
Given the increased use of brain scans, cranial MRA/3D-CTA, and other minimally-invasive diagnostic imaging techniques, there has been a sharp increase in patients unexpectedly diagnosed with unruptured intracranial aneurysms (UIA) [
When a UIA is detected, people face an uncertain situation. Beginning from the time before the development of symptoms, an individual is aware of the potential dangers of this illness. People who are asymptomatic and have been diagnosed with a UIA unexpectedly, become aware of its existence with inadequate psychological preparation, and consequently start to show an increase in uncertainty [
Despite the development of a Japanese version [
Therefore, this study focuses on the general idea of uncertainty concerning the subjective interpretations of responses to illness and medical treatment. A scale is also developed to measure the uncertainty that affects patients who have undergone endovascular surgery to treat a UIA, and to assess the scale’s validity and reliability.
Definition of UncertaintyThe definition of uncertainty in this study is based on Mishel’s definition as “the inability to determine the meaning of illness-related events…, the cognitive state created when the person cannot adequately structure or categorize an event because of the lack of sufficient cues” [
The name of the measure being developed and evaluated is the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (henceforth referred to as the UUIACS).
An item pool was compiled with passages describing uncertainty, which had been excerpted from interview data of 31 patients diagnosed with UIA at the Department of Neurosurgery at Metropolitan A University Hospital. The interviewed patients had no previous experience of surgery related to intracranial aneurysms, and were undergoing endovascular coiling for the first time. Questions were developed using existing scales that measure uncertainty: the Mishel Uncertainty in Illness Scale-Community Form (MUIS-A) [
Next, similar and overlapping content were clustered, and 52 questions were developed. The questions were classified based on their meaning and organized into 6 categories: 1) Nature of the disease; 2) The treatment characteristics; 3) Information; 4) Decision making; 5) Course of the future; and 6) Living with UIA [
The 52 questions were checked by another researcher, two doctors, two nurses, and four patients who previously underwent endovascular coiling to ensure that the expressions used were appropriate; some revisions were made. The questionnaire consisted of 52 items each with five response options (strongly disagree, disagree, undecided, agree, strongly agree) rated on a scale of 1 - 5 points. Pilot tests were conducted with 50 UIA patients. The analysis found that two questions had a ceiling effect (percentage of patients who scored at the ceiling level―that corresponded to 10% best results on the scale), and one had a floor effect (percentage of patients who scored at floor level―equivalent to the 10% worst results on the scale); these items were eliminated, leaving the questionnaire with 49 questions. Additionally, a final analysis was performed to confirm the internal consistency and wording of the scale. In the end, the original draft of the UUIACS had 6 categories and 49 questions.
The survey portion of the UUIACS was distributed to develop it and analyze its validity and reliability. Exploratory factor analysis, internal consistency, validity testing, and confirmatory factor analysis were performed on the survey.
The survey was administered at two different institutions to convenience samples of UIA patients who underwent neurosurgery and endovascular coiling as part of their treatment. The candidates in the target group were patients who were undergoing endovascular coiling for the first time and had consented to participate in the study.
Patients’ gender, age, smoking behavior, family composition, medical history, and other patient attributes were surveyed via medical examination and patient interviews. The first author performed structured interviews. The content of the question included smoking behavior, family composition, medical history, and circumstances of discovery.
The original draft of the UUIACS consisted of 6 categories and 49 questions, with responses on a 5-point scale (strongly disagree, disagree, undecided, agree, strongly agree) ranging from 1 - 5 respectively. The total and subscale scores were calculated by simply summing the scores, a higher score indicated a higher degree of uncertainty experienced.
1) Universal Uncertainty in Illness Scale (UUIS)
The UUIS, developed by [
2) Health Locus of Control Scale (HLC Scale)
The HLC scale [
3) Short Form-36v2® Health Survey-Japanese Version (SF-36v2®)
The SF-36v2® survey [
A questionnaire survey method was used. The researchers explained the intent of the survey and any ethical considerations to the patients. After obtaining informed consent, the questionnaires were distributed and the participants’ responses were requested. The responses were collected on the same day, or they were returned by mail. The data collection was conducted from July 2013 to March 2014.
The following analyses were performed using statistics software SPSS 21.0J and Amos 22.0J. Item analysis was used to examine ceiling and floor effects and item-total correlations. Construct validity was tested by comparing the 6 categories that were developed when composing the original draft with the factors that were extracted from exploratory factor analysis. Criterion-related validity was tested by analyzing the correlation coefficients using UUIS, the HLC scale, and the Japanese version of the SF36v2®. Internal consistency was assessed by calculating Cronbach’s alpha coefficients for the entire scale and each subscale. The model’s degree of conformance was examined using confirmatory factor analysis, which was performed on the latent variables that included the items of the UUIACS that were selected as factors as a result of exploratory factor analysis. The UUIACS model’s degree of conformance was tested using the goodness of fit index (GFI), degree-of-freedom adjusted goodness of fit index (AGFI), comparative fit indicator (CFI), and root mean square error of approximation (RMSEA).
This study was conducted with the approval of the medical ethics committees of the institutions that implemented the survey in June 2013. The participants gave their consent after the study’s intent was explained to them. At that time, the freedom of the participants to withdraw from the study and the protection of their anonymity were explained verbally and in writing, after which signatures were obtained indicating their consent. Their responses to the questionnaire were collected on the same day, and when this was not possible, the questionnaire was taken home and returned by mail.
A request for cooperation was made to two institutions, both of which agreed. Questionnaires were distributed to 201 participants and 173 were retrieved (68.1% return rate); 10 of the returned questionnaires had missing responses; 9 of them were missing fewer than 10% of the total responses. Therefore, the total score was adjusted to reflect the average of the UUIACS, UUIS, HLC scale, and SF-36v2® (Japanese version). One of the returned questionnaires was missing more than 10% of the total responses and was eliminated from the study. Valid responses from 172 patients were used in the analysis of the data (response rate: 99.4%).
As shown in
The item-total correlations ranged from 0.22 to 0.64; none of the questions had a correlation coefficient below 0.2; therefore, none of them were trimmed. Descriptive statistics were calculated and 15 questions were eliminated: 8 questions had ceiling effects (e.g. “I do not know the cause of my intracranial aneurysm”) and 7 questions had floor effects (e.g. “I have not decided whether to continue medical examination going forward”).
Exploratory factor analysis using promax rotation, was conducted on 34 questions (after eliminating 15 questions) (
| Number | Proportion (%) | ||
|---|---|---|---|
| Age | Mean ± SD | 62.3 ± 10.9 | |
| Sex | Male | 54 | 31.4 |
| Female | 118 | 68.6 | |
| Employed | Yes | 99 | 57.6 |
| No | 73 | 42.4 | |
| High blood pressure | Yes | 82 | 47.7 |
| No | 90 | 52.3 | |
| Smoker | Yes | 55 | 32.0 |
| No | 117 | 68.0 | |
| Drinks alcohol | Yes | 62 | 36.0 |
| No | 110 | 64.0 | |
| Family history | Yes | 44 | 25.6 |
| No | 128 | 74.4 | |
| Circumstances of discovery | Screening for UIA | 123 | 71.5 |
| Symptoms | 49 | 28.5 | |
| Sizea | Mean ± SD | 4.9 ± 2.1 | |
| 5 mm or more | 69 | 40.1 | |
| Less than 5 mm | 103 | 59.9 |
aAlternate option for UIA size was >5 mm.
eliminating questions with a factor loading of less than 0.4, as shown in
The contents of the items selected for each of the four extracted factors were interpreted. The first factor (6 items) pertained to uncertainty concerning the complexity of decision making (e.g. “I do not know which to choose, endovascular surgery or craniotomy” and “I do not know whether it is good that the unruptured intracranial aneurysm was detected”). This factor was named “Lack of decision-making cues”. The second factor (5 items) pertained to uncertainty about the lack of information and the interpretation of information (e.g. “I feel like the more I learn about my illness and treatment, the less I understand and the more questions mount up” and “I do not know what other people with the same illness may be experiencing”). This factor was named “Lack of information, complexity of information interpretation”. The third factor (3 items) pertained to uncertainty about the inability to specify the nature of the illness, as it was discovered at an asymptomatic stage before a rupture (e.g. “I do not know whether or not an unruptured intracranial aneurysm is an illness”). This factor was named “The ambiguous nature of the disease”. The fourth factor (3 items) pertained to uncertainty about living with a UIA because it is a relatively recent illness (e.g. “Unruptured intracranial aneurysm is an illness with which I am not very familiar”). This factor was named “The unpredictable living with UIA”.
Cronbach’s alpha for the overall UUIACS (17 questions) was 0.84, and for each of the four factors, it ranged from 0.61 - 0.82 (
The items that fell under the four factors extracted through exploratory factor analysis (1) “Lack of decision-