Chapter 4 A CONCEPTUAL MODEL FOR TB ADHERENCE FACTORS
4.3 TB Adherence Factors Model Design
4.3.1 Factor Type
Factor Type represents the grouping of influencing factors according to similarity of common terms as presented in the literature. This type of grouping enables the creation of a category, sometimes in a hierarchy, to assist in distinguishing terms. It is a common dimension for categorizing influencing factors.
The classifications found in the three existing studies were used to develop unique and specific Factor Type categories. The existing categories were restructured to eliminate concept overlaps and misrepresented factors. They were iteratively checked in terms of their effectiveness to classify factors found in scientific publications.
The process of restructuring the categories involves matching existing categories based on similarity of names and meaning. Similar Factor Type categories were merged to produce a comprehensive category.
Also, some of the broad categories that represent heterogeneous factors were split to produce unique categories without unnecessary overlap. Through this process, seven Factor Types were defined and their boundaries were set to facilitate the inclusion of factors from scientific evidence. They are patient- centred, social, economic, therapy-related, health system, lifestyle and geographical access.
A hierarchical model was introduced to capture the Factor Type in a consistent manner. The top level of the hierarchy includes the main categories while the second level represents sub-groups of factors.
This second level is generated from ad-hoc groupings found in existing studies. The lowest level in the hierarchy will represent concrete and measurable influencing factors.
4.3.1.1 Patient Centred
The new Patient-Centred category of this conceptual model was created by merging related categories and was redefined. The term “Patient-Centred” was taken from the study by Jin et al [28] as against
“patient-related” in WHO [1] and Munro et al.’s [8] “personal character”. This category also reflects the definition given by Munro et al. The new Patient-Centred category is defined as the category of influencing factors based on the demographic attributes of patients and the attitudes that define the characteristics of the patients. Table 4.3 shows the list of factors identified from SSA studies that were included in the category.
Main Class Middle Class Bottom Class Patient centered Demographic Age group
Gender Marital Status Knowledge Knowledge of TB
Education level Psychology Emotional state
Psychiatric condition Depression
Table 4.3: Three level hierarchy of patient-centred influencing factors
The Patient-Centred category of this conceptual model includes demographic and psychological factors, but excludes social-related factors from the definitions presented by Jin et al and Munro et al.
Demographic information and knowledge/literacy of patients, as included by Jin et al and Munro et al, fits into the category of patient-centred factors. Interpretation of wellness and illness, motivation and beliefs [8] [28] were excluded because they align more with the social perspectives of the patient.
Compliance history and substance abuse, included in Jin et al, were excluded because they are therapy and lifestyle-related factors respectively.
4.3.1.2 Social and Economic
The studies of Jin et al and WHO group social context factors and economic factors into the socio- economic category. The example of Munro et al. was followed by separating economic factors from the social factors. This will allow for a unique representation of the factors in a specific category and reveal the potential of a factor to belong to more than one category.
The Social Factor category of the conceptual model represents the social context and situation of a patient, while the Economic Factor category of the conceptual model relates to the economic status and condition of the patient. The Social Factor category includes stigma, social network and belief-related factors. Economic Factors include financial burden, employment status, and basic amenity-related factors (Table 4.4).
Main Class Middle Class Bottom Class
Economic Finance Income class
Poverty Employment Job class
Employment status Basic amenities Lack of food
Homelessness Social Social network Family support
Community network Stigma related Perceived stigma
Experienced stigma
Belief Wellness perceived as cured Treatment efficacy belief
Table 4.4: Three level hierarchy of economic and social influencing factors 4.3.1.3 Therapy Related
The Therapy-related factor category of the conceptual model was adopted from WHO and Jin et al. It represents the category of influencing factors that relate to therapy difficulties faced by patients and clinical procedures that facilitate or hinder patients from adhering to treatment. It also forms part of the disease-related factor presented by Jin et al and the health service category of Munro et al. See Table 4.5.
Main Class Middle Class Bottom Class Therapy Therapy effect Drug adverse effect
Symptoms persistence Co-morbidity HIV co-infection Treatment Defaulting history
Treatment alternative
Table 4.5: Three level hierarchy of therapy-related influencing factors
Co-morbidity with other chronic diseases is an important factor included in the therapy category because it deals with patients’ concurrently undergoing treatment for multiple diseases. These patients face many challenges which could be a clash of clinical appointments and the burden of medication.
4.3.1.4 Health System-Related
The Health System category of the conceptual model consists of influencing factors that relate to the performance of healthcare providers and the accessibility of healthcare services to patients at the health facilities, as shown in Table 4.6. The Health System category is directly represented in categorizations by Jin et al and WHO. This category partially covers the system-related factors represented in the health service category, as defined by Munro et al.
Main Class Middle Class Bottom Class
Health system Healthcare facility Opening hour favorability Drug availability
Healthcare staff Staff friendliness
Communication gap experience Table 4.6: Three level hierarchy of health system-related influencing factors 4.3.1.5 Lifestyle Related
Some influencing factors are directly associated with the lifestyle of the patient, e.g. substance abuse, diet and exercise. These factors are grouped into a new category of the conceptual model termed
“Lifestyle”, see Table 4.7. These are circumstantial factors related to habits developed by patients and are subject to change. They have been represented under various categories. Jin et al classified some of these factors as patient-centred, while WHO classified them as condition-related factors. Separating
these factors into different categories will allow for a clear identification of unhealthy lifestyle-related factors. The Lifestyle factor category distinctly covers those factors related to a patient’s lifestyle.
Main Class Middle Class Bottom Class Lifestyle Substance abuse Alcohol consumption
Tobacco usage Hard drug usage Healthy living Diet
Exercise
Table 4.7: Three level hierarchy of lifestyle-related influencing factors 4.3.1.6 Geographic Access Related
A Geographical Access category was also introduced in the conceptual model to represent the category of influencing factors that relate to the location of healthcare facilities, the house/workplace of patients and accessibility-related costs in terms of distance, time and effort, and financial expenses (Table 4.8).
This will help in understanding both the financial and non-financial burden that relate to a patient’s geographical access to health facilities.
Main Class Middle Class Bottom Class Geographical
access
Location Distance to facility Dwelling region Transportation Travel time
Transportation cost
Table 4.8: Three level hierarchy of geographical access influencing factors