Breathing Problems Questionnaire Research Articles

Adaptação cultural e reprodutibilidade do questionário para problemas respiratórios em pacientes portadores de DPOC no Brasil

To translate the Breathing Problems Questionnaire (BPQ) into Portuguese and adapt it to the Brazilian culture, as well as to evaluate its reproducibility in patients with COPD. After the BPQ had been translated and adapted to the Brazilian culture, it was administered to a subgroup of 8 patients in order to identify their uncertainties and difficulties. The questionnaire was reviewed by an expert committee, and its final version was arrived at. A second translator back-translated the final version into English, which was sent to the original author in order to verify that the original meaning of the questionnaire had been maintained. After the approval of the original author, the final Portuguese-language version of the questionnaire was administered to 50 patients with COPD, in order to evaluate its reproducibility. The mean response time was 9.5 min. Of the 50 patients, 21 were female and 29 were male. The mean age was 65.8 ± 7.5 years. Most of the patients were classified as having moderate COPD (29.16%) or severe COPD (52%). The intraclass correlation coefficient (ICC) for the total score was 0.94. The ICCs for the eleven BPQ domains and its two subscales were also above 0.70. Moderate correlations were found between the BPQ domains and subscales. The translation and cultural adaptation of the BPQ for use in Brazil was deemed appropriate, because the patients could easily understand and answer the questions. In addition, the Brazilian version of the BPQ questionnaire was found to be reliable, showing good reproducibility.

ABS63: Pulmonary rehabilitation in the community is effective, but benefits may be distorted by methods of analysis

Pulmonary rehabilitation (PR) programmes are increasingly community based, being run by health professionals who may have limited experience of reporting outcomes. The way patient outcome data is analysed and presented can distort the benefits of PR. PR programme reports are increasingly used to justify investment. It is important that they are accurate. To assess the benefits of community based PR, and compare the impact of two methods of analysis on the magnitude of observed improvements. COPD patients seen by the Plymouth PR programme: baseline assessment; 7 weekly sessions and follow up. Outcome Assessments: Shuttle walking test distance (SWT), Chronic Respiratory Disease Questionnaire (CRDQ): Breathing Problems Questionnaire (BPQ) at baseline and 7 weeks. Analysis of results of all patients attending at each stage including those who subsequently dropped out (group means) were compared to means of individual changes from baseline. 183 patients were assessed, 151 completed the programme. Mean FEV1 at baseline: 1.05∓0.4 (n= 117). Mean changes in: SWT (metres) Group 62.8m, individual 51.2 m. Total CRDQ: Group 14.1, individual 13.2; HADS Anxiety: Group −1.3, individual −1.3 Depression: Group −0.8, individual −0.6. SBPQ: Group −1.1, individual −0.7. The mean baseline scores in those who dropped out were lower than means for those who completed the programme, for instance mean SWT of completers was 183m, but drop outs was 124m (p = 0.009). Outcome measures from a once weekly, community PR programme demonstrate changes comparable to those of hospital based programmes. The analysis of outcomes should report mean individual changes rather than mean changes between the group attending at baseline and those completing the programme. The difference reflects that those with severe illness are more likely to drop out. This can lead to improvements in outcome being wrongly attributed to the PR programme. Conflict of interest and funding Dr Jones receives educational or research grants from GSK; Astra Zeneca; Boehringer-Ingelheim; Pfizer; Ivax; Altana.

Predictors of 1-year mortality in patients discharged from hospital following acute exacerbation of chronic obstructive pulmonary disease

acute exacerbation of COPD (AECOPD) is a major cause of hospital admission, and predicts subsequent medium-term mortality. We aimed to examine mortality predictors in patients discharged from hospital after AECOPD. we obtained baseline demographic and clinical data from 100 patients (mean age (range)=73 (60-98) years; 48 males) admitted with AECOPD. All completed the following validated questionnaires: a quality of life questionnaire (Breathing Problems Questionnaire; BPQ); a screening questionnaire for depression (Brief Assessment Schedule Depression Cards; BASDEC); a disability questionnaire (Manchester Respiratory Activities of Daily Living questionnaire; MRADL). Following discharge all were prospectively followed and survival/mortality at 12 months confirmed from hospital notes and by contacting general practitioners. the prevalence of depression at recruitment was 56%. One-year mortality in the whole group was 36%. Odds ratios (95% confidence intervals) for mortality predictors (univariate logistic regression analysis) were: use of long-term oxygen therapy=2.72 (1.06-6.97); subsequent readmission=2.57 (1.08-6.12); MRADL score=0.87 (0.80-0.94) (disability predicting death); BASDEC score=1.13 (1.02-1.26) (depression predicting death); BPQ score=1.08 (1.04-1.12) (low quality of life predicting death); length of original hospital stay=1.03 (1.00-1.07). On multivariate logistic regression analysis the only mortality predictor was BPQ with an odds ratio (95% confidence limits) of 1.13 (1.04-1.22). In terms of mortality prediction for individuals, a threshold MRADL score of <12 gave a sensitivity of 86%, specificity of 55%, positive predictive value of 88% and negative predictive value of 52%, with similar predictive values using BPQ as an independent variable. 1-year mortality after AECOPD admission is high. The presence of depressive illness (which is extremely common), and levels of both disability and impairment of quality of life are univariate predictors of 1-year mortality in this patient group. This model may be useful in predicting prognosis for individuals and thus in guiding treatment decisions.

Physical and emotional aspects of self–reported health status: a two–factor model of the short–form BreathingProblems Questionnaire

The short version of the Breathing Problems Questionnaire (BPQ) is used as an outcome tool in pulmonary assessment. The aim of the study was to establish the validity of scoring BPQ with two subscales, reflecting emotional and physical components of health-related quality of life (HRQoL). Two subscales were suggested by exploratory factor analysis conducted on a data set of 97 patients with chronic obstructive pulmonary disease (COPD). Both subscales were significantly associated with the 6 minute walk test, total quality of life, and emotional stability. Only the physical subscale was significantly associated with FEV1, and only the emotional subscale was significantly associated with happiness. Overall, the sizes of the different correlations are consistent with the conceptual differentiation of the two subscales. We suggest that evaluation of rehabilitation can be made with the two subscales as well as an overall score of the BPQ.

Prevalence of sub-threshold depression in elderly patients with chronic obstructive pulmonary disease.

We hypothesized that COPD patients with sub-threshold depression would have levels of disability and impaired quality of life approaching that for major depression and significantly greater than for non-depressed COPD patients. A university teaching hospital 137 outpatients (69 men), with a mean age of 73 years (range 60-89 years) with symptomatic irreversible, moderate to severe COPD were recruited. Subjects were interviewed using the Geriatric Mental State Schedule (GMS), a structured psychiatric interview schedule, along with its diagnostic algorithm AGECAT. A GMS/AGECAT score of 3 or more is indicative of a case-level of depression, a GMS/AGECAT score of 1-2 indicates sub-threshold depression and GMS/AGECAT of 0, no depression. Physical disability was measured by the Manchester Respiratory Activities of Daily Living questionnaire (MRADL) and quality of life was assessed by the Breathing Problems Questionnaire (BPQ). Mean (SD) one second forced expiratory volume was 0.89 (0.33) litres. The prevalence of GMS/AGECAT case-level depression (>or= 3) was 57 cases (42%); of GMS/AGECAT sub-threshold depression (1-2) 34 (25%); and GMS/AGECAT non-depression (0) 46 (33%). Comparison of MRADL score in the three groups (mean, 95% confidence intervals) revealed [GMS >or= 3 = 9.9 (8.4 to 11.3) vs GMS = 1-2, 12.9 (11.2 to 14.4) vs GMS = 0, 15.6 (14 to 16.6) p < 0.0001]. BPQ scores (mean, 95% confidence intervals) showed [GMS >or= 3 = 54 (50 to 57) vs GMS = 1-2, 40 (36.3 to 44) GMS = 0, 33 (30.6 to 36.7) p < 0.0001]. There was no significant difference in FEV(1) between the three groups. Sub-threshold depression accounted for 25% of the sample. In this study disability associated with sub-threshold depression in patients with COPD was intermediate to that associated with case-level depression and no with depression and significantly worse than in the latter group. Sub-threshold depression is associated with substantial morbidity in COPD.

Analysis of the factors related to mortality in chronic obstructive pulmonary disease: role of exercise capacity and health status.

In this study, we analyzed the relationships of exercise capacity and health status to mortality in patients with chronic obstructive pulmonary disease (COPD). We recruited 150 male outpatients with stable COPD with a mean postbronchodilator FEV1 at 47.4% of predicted. Their pulmonary function, progressive cycle ergometry, and health status using the Chronic Respiratory Disease Questionnaire, the St. George's Respiratory Questionnaire (SGRQ), and the Breathing Problems Questionnaire were measured at entry. Among 144 patients who were available for the 5-year follow-up, 31 had died. Univariate Cox proportional hazards analysis revealed that the SGRQ total score and the Breathing Problems Questionnaire were significantly correlated with mortality; however, with the Chronic Respiratory Disease Questionnaire, the total score was not significantly correlated. Multivariate Cox proportional hazards analysis revealed that the peak oxygen uptake and the SGRQ total score were both predictive of mortality, independent of FEV1 and age. Stepwise Cox proportional hazards analysis revealed that the peak oxygen uptake was the most significant predictor of mortality. We found that exercise capacity and health status were significantly correlated with mortality, although different health status measures had different abilities to predict mortality. These results will have a potentially great impact on the multidimensional evaluation of disease severity in COPD.

Anxiety and Panic in Chronic Obstructive Pulmonary Disease: The Role of Catastrophic Thoughts

A short form of the Interpretation of Breathing Problems Questionnaire (the IBPQ-S) was developed in 30 patients with chronic obstructive pulmonary disease (COPD). It was then used to test specific hypotheses, derived from Clark's cognitive model of panic (D. Clark, 1986). Findings indicated that IBPQ-S catastrophic cognitions were related to anxiety triggered by COPD symptoms but not to general anxiety, or to panic. Severity of IBPQ-S catastrophic cognitions contributed unique variance to the prediction of anxiety triggered by COPD symptoms (in safe and unsafe situations), and to the prediction of behavioral avoidance in unsafe situations. In all 3 cases IBPQ-S cognitive variables added significant incremental variance beyond that explained by disease, demographic variables, and the Agoraphobic Cognitions Questionnaire. The measure also has promising psychometric properties. The findings are consistent with Clark's model; they highlight the importance of catastrophic cognitions in COPD-related anxiety.

A randomised controlled trial of four weeks versus seven weeks of pulmonary rehabilitation in chronic obstructive pulmonary disease

BACKGROUNDPulmonary rehabilitation programmes have been shown to improve both exercise tolerance and health status in patients with chronic obstructive pulmonary disease (COPD). The optimal duration for a pulmonary rehabilitation programme...

A comparison of three disease-specific and two generic health-status measures to evaluate the outcome of pulmonary rehabilitation in COPD

The use of health status as an outcome measure is becoming more widespread in pulmonary rehabilitation. There are a number of health status measures but the choice remains uncertain. Three disease specific measures and two generic measures of health status were employed to observe their relative sensitivity to a 7-week course of pulmonary rehabilitation.Patients with stable chronic obstructive pulmonary disease (COPD) were recruited into a rehabilitation programme. They completed a shuttle-walking test and three disease-specific questionnaires: the Chronic Respiratory Questionnaire (CRQ), the St. George's Hospital Respiratory Questionnaire (SGRQ) and the Breathing Problems Questionnaire (BPQ). Patients also completed two generic questionnaires: a global quality-of-life scale and an activity checklist. Ninety-seven patients [58 male mean (SD) age 67 (8·7) years] completed the course over a 12-month period. The mean pre-rehabilitation (SD) FEV1was 1·06 (0·59)l. The shuttle-walking test and the treadmill-endurance test increased significantly after rehabilitation (P<0·001). All three disease-specific questionnaires improved significantly (the CRQ and SGRQ improved beyond minimum clinically important difference). The global score improved significantly whilst the ‘things people do’ decreased.All three disease-specific measures were responsive to pulmonary rehabilitation. However the operator-led CRQ appears to be the most sensitive short-term outcome measure.

The Manchester Respiratory Activities of Daily Living Questionnaire: Development, Reliability, Validity, and Responsiveness to Pulmonary Rehabilitation

Because there is no respiratory-specific activities of daily living (ADL) scale for use in older patients, our aim was to design and develop the Manchester Respiratory ADL questionnaire (MRADL) and to assess its validity in older patients with chronic obstructive pulmonary disease (COPD). The MRADL is a composite of the most discriminative questions from the Nottingham Extended ADL Questionnaire (NEADL) and the Breathing Problems Questionnaire (BPQ). A University teaching hospital. Participants were 188 (104 men) COPD out-patients aged 60 to 93 (mean 77) years and 55 (23 men) normal controls (NCs) aged 70 to 90 (mean 78) years. Exclusions were confusion and acute respiratory exacerbation/use of oral corticosteroid within 6 weeks. A subgroup of COPD subjects completed a pulmonary rehabilitation program (PR) to assess responsiveness of the MRADL to intervention. All subjects completed MRADL and NEADL scales, and 15 COPD subjects (11 men) completed an 8-week PR program. Mean (SE) 1-second forced expiratory volume (FEV1) in COPD subjects was 0.94 (0.03) liters, and in NCs it was 1.96 (0.07) liters. MRADL discriminated better between COPDs and NCs than did the NEADL in terms of sensitivity (90% vs 76%; X2 = 4.8, P = .02) and negative predictive value (84% vs 69%; X2 = 4.5, P = .03). MRADL responded to changes during PR: pre versus post mean (SE) score 11.2 (1.1) vs 13.4 (1.1); (t = 3.09; P = .008), but NEADL was unchanged. MRADL showed high consistency (Cronbach alpha 0.91). 95% confidence limits of repeatability were -0.63 to +0.26 (P = .42) for MRADL and -0.53 to +0.26 (P = .50) for NEADL. MRADL is a reliable and valid self-report scale for assessment of physical disability in older COPD patients. It is responsive to pulmonary rehabilitation.

Comparison of Discriminative Properties Among Disease-Specific Questionnaires for Measuring Health-Related Quality of Life in Patients With Chronic Obstructive Pulmonary Disease

Three disease-specific, health-related quality of life (HRQL) questionnaires have been introduced to assess patients with chronic obstructive pulmonary disease (COPD): the St. George's Respiratory Questionnaire (SGRQ), the Breathing Problems Questionnaire (BPQ), and the Chronic Respiratory Disease Questionnaire (CRQ). The purpose of the present study was to make comparisons between the SGRQ, the BPQ, and the CRQ in their discriminative properties, and to clarify the characteristics of each questionnaire. One hundred forty-three patients with mild to severe COPD completed pulmonary function tests, progressive cycle ergometer testing for exercise capacity, assessment of dyspnea, anxiety, and depression, and assessment of HRQL. The frequency distributions of the questionnaire scores showed that the SGRQ and the CRQ were normally distributed and that the BPQ was skewed toward low scores. Relationships between all dimensions of the three questionnaires were significant (correlation coefficients [Rs] = 0.74 to 0.86). The three questionnaires had significant but weak correlations (Rs = -0.24 to -0.36) with some physiologic variables (VC, FEV1, and DL(CO)/VA) and mild to moderate correlations with exercise capacity and assessment of dyspnea, anxiety, and depression. Stepwise multiple regression analyses revealed that the Baseline Dyspnea Index (BDI) score, anxiety by the Hospital Anxiety Depression Scale (HAD), and maximal oxygen uptake (VO2max) accounted for 61% of the variance in the SGRQ and that the BDI and anxiety of the HAD accounted for 53 and 49% of the variance in the BPQ and the CRQ, respectively. Dyspnea and psychologic status impacted the HRQL in patients with COPD. Although no substantial differences between the SGRQ, the BPQ, and the CRQ were evident in the correlations with physiologic parameters and the influential factors, the BPQ was found to be less discriminatory than the SGRQ and the CRQ in evaluating HRQL cross-sectionally.

Quality of life in elderly patients with COPD: measurement and predictive factors

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity in old age. It leads to reduced quality of life (QoL), but the factors that contribute to this are less understood. There is no consensus on measurement of QoL in elderly COPD patients. We assessed (a) factors predicting QoL in elderly COPD out-patients and (b) specificity (SP), sensitivity (SEN), positive and negative predictive values (PPV and NPV) and repeatability of two disease-specific QoL instruments, the Chronic Respiratory Disease Questionnaire (CRQ) and the Breathing Problems Questionnaire (BPQ) in elderly people. All subjects also completed an ADL measure [Nottingham Extended ADL (NEADL)] and a measure of psychological well-being [Brief Assessment of Depression Cards [BASDEC)] as well as a 6-min walk test. Subjects comprised 96 (56 men) elderly out-patients with irreversible COPD aged 70–93 years (mean 78) who were clinically stable for ≥ 6 weeks. Controls were 55 (23 men) aged 71–90 years (mean 78) with normal lung function. All were cognitively intact. Mean FEV 1/FVC in COPD subjects was 45·5 ( se=1·4)% and for controls was 71·4 ( se=1·3)%. Repeatability was good for both BPQ and CRQ with no significant difference. There were no significant differences in specificity and positive predictive values between the two questionnaires but BPQ performed better than CRQ with regard to sensitivity ( P=0·02) and NPV ( P<0·001). A multiple regression analysis was used to identify variables that best predicted BPQ and CRQ in COPD subjects. For BPQ predictive values were NEADL ( P<0·0001); BASDEC ( P<0·0001); age ( P<0·0001); 6-min walk distance ( P=0·001); body mass index ( P<0·05); resting oxygen saturation ( P<0·05); and household composition (living alone or with relatives, P=0·05). In contrast only the following predicted CRQ: NEADL, BASDEC and resting oxygen saturation. Sixteen per cent of the variance in BPQ was accounted for by NEADL score, 9% by BASDEC, 4% by age and 3% by 6-min walk distance (total r 2=0·70). It was concluded that: (1) BPQ provides more valid assessment than CRQ of QoL in elderly COPD subjects; (2) severity of disease in terms of its impact on QoL is not predicted by lung function tests; (3) the most important determinants of QoL are ADL score and emotional status.

A short outpatient pulmonary rehabilitation programme: immediate and longer term effects on exercise performance and quality of life

Pulmonary rehabilitation is widely available in North America and parts of Europe for patients with chronic obstructive pulmonary disease (COPD). Here, we describe the feasibility and benefits of providing a comprehensive but cost effective pulmonary rehabilitation programme in a U.K. district general hospital. Two hundred and sixty-seven patients with respiratory disability were referred for pulmonary rehabilitation. Patients were assessed and recruited onto a 7 week outpatient-based pulmonary rehabilitation programme including elements of exercise and education without longer term maintenance. Exercise performance was measured by the shuttle walking test and a treadmill endurance test, and quality of life as measured by two disease specific questionnaires, the Breathing Problems Questionnaire and the Chronic Respiratory Disease Questionnaire. Of 267 patients referred between 1993 and 1996, 132 (110 with COPD) have completed rehabilitation and could be evaluated. For all graduates, shuttle distance increased by 58 m (27%) and treadmill endurance time increased by 15·9 min (294%). The Breathing Problems Questionnaire proved sensitive to changes in quality of life in some domains. The Chronic Respiratory Disease Questionnaire showed significant improvements in all domains in a sub-set of 57 patients who completed it. Longer term follow-up of 49 patients at a mean of 10·3 months following pulmonary rehabilitation revealed that previous gains in exercise performance and quality of life were maintained with improvements in shuttle walking distance of 33 m (14% over baseline) and endurance time of 16 min (280% over baseline). The Breathing Problems Questionnaire showed no overall change but the Chronic Respiratory Disease Questionnaire showed continued improvement in a small number of patients. We therefore concluded that a short outpatient based pulmonary rehabilitation programme without a maintenance element has produced significant gains in exercise performance and quality of life for 132 patients at a district general hospital in the U.K.

Health-related quality of life in patients with chronic obstructive pulmonary disease.

Health-related quality of life is usually impaired in patients with moderate to severe chronic obstructive pulmonary disease. The Sickness Impact Profile, the Medical Outcome Study "short form" 36, and the Nottingham Health Profile have all been used as generic measures of health-related quality of life. Although the discriminative properties of three disease-specific instruments, the Chronic Respiratory Disease Questionnaire, the St. George's Respiratory Questionnaire, and the Breathing Problems Questionnaire, are similar, the responsiveness of the Chronic Respiratory Disease Questionnaire and the St. George's Respiratory Questionnaire has been the most clearly demonstrated. The characteristics of each instrument should be considered in the selection of specific health-related quality of life questionnaires for clinical research.

Development of a shortened version of the Breathing Problems Questionnaire suitable for use in a pulmonary rehabilitation clinic: a purpose-specific, disease-specific questionnaire.

One hundred and thirty-eight chronic obstructive pulmonary disease (COPD) patients completed the Breathing Problems Questionnaire (BPQ) before and after a comprehensive programme of rehabilitation. Examination of the changes on individual items showed improvement on 22 items, of which four items were significant at p < 0.05 and deterioration on nine items, of which two were significant at p < 0.01. All deteriorating items were consistent with lifestyle adaptations encouraged as part of the rehabilitation programme. We examined the psychometric properties of a reduced ten item version of the BPQ limited to the items most sensitive to change. We recommend the purpose-specific, disease-specific COPD scale for measuring change in pulmonary rehabilitation assessment in contrast to the longer 33 item questionnaire, which, however, may be more useful for cross-sectional assessment.

A comparison of the Barthel index and Nottingham extended activities of daily living scale in the assessment of disability in chronic airflow limitation in old age

there is no disease-specific instrument for measuring activities of daily living (ADLs) in elderly patients with chronic airflow limitation (CAL). We assessed sensitivity, specificity and positive and negative predictive values of two ADL scales: the Barthel index and the Nottingham extended ADL scale in elderly people with and without CAL. the Breathing Problems Questionnaire was used as a measure of quality of life (a low score indicates good quality of life) in 96 outpatients (56 men) with CAL aged 70–93 (mean 78) years and 55 community-dwelling controls (23 men) aged 71–90 (mean 78) years with normal lung function drawn from a recent community survey. CAL subjects had been clinically stable for >6 weeks. All subjects were cognitively intact. mean best 1 s forced expiratory volume/forced vital capacity was 45.5% (SE 1.4) in CAL subjects and 71.4% (SE 1.3) in controls. All CAL subjects considered themselves disabled and had higher breathing questionnaire scores [geometric mean scores: 395 (range 13–112) vs 4.8 (range 0.6–40) for controls; t= 13.4, P<0.0001]. However, the Nottingham extended ADL index (threshold >18) discriminated better than the Barthel index (threshold >17) in terms of sensitivity (76% vs 19%; x2=60.9, P< 0.0001) and negative predictive value (75% vs 40%; x2=20.2, P<0.0001). Altering the Barthel threshold did not improve its performance. Multiple regression analysis showed that variability in physiological and psychological variables related to CAL predicted variability in Nottingham extended ADL score (R2=0.71) but not in Barthel score. the Barthel index underestimates disability in CAL in old age. The Nottingham extended ADL discriminates better between normal old people and those with CAL.

Predictors of Functional Disability in Elderly Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and disability in old age. It leads to reduced functional activities, but factors that contribute to this are less well understood. This study investigated factors that predict functional disability in elderly patients with COPD. A structured questionnaire was used to extract demographic dafa. Subjects performed spirometry and a six-minute walk test and completed the Nottingham Extended Activities of Daily Living Index (NEADL), a depression screening q uestionnaire, the Brief Assessment Schedule Depression Cards (BASDEC), and a disease-specific quality of life questionnaire the Breathing Problems Questionnaire (BPQ). Subjects comprised 96 (56 men) out-patients with COPD, aged 70-93 (mean 78) years. COPD subjects were clinically stable (no hospital admission or

Domains, constructs and the development of the breathing problems questionnaire.

Health-related quality of life (QoL) questionnaires are commonly developed as content valid instruments with conventionally defined domain subscales. We contrasted content valid domain subscales with construct valid construct subscales and developed a 13-domain QoL questionnaire, the Breathing Problems Questionnaire (BPQ), for patients with chronic bronchitis. In a series of studies, we examined the constructs relevant to COPD patients' experience of health. First, we provided psychometric evidence that items in the BPQ form two distinct groups: functional problems and negative evaluations. Second, we showed that problems were significantly more correlated with morbidity whereas negative evaluations were significantly more correlated with neuroticism. Third, we showed that negative evaluations correlated with neuroticism whereas positive evaluations (measured by the Satisfaction with Illness Scale) correlated with extraversion. Patients are more likely to make positive evaluations of their illness when they recognize that they are seriously ill. Most of the BPQ domains are subcategories of the construct of problems: both domains and construct classifications provide useful information.