Identification of studies .1 Search string development

Although some organisations, such as the Cochrane Collaboration and NHS CRD, have developed some common search strings (for example, for identifying health economic evaluations or RCTs), given the vast scope of the literature potentially relevant to this review, none fitted the wide searching requirements.

Instead, review-specific searches were developed based on content keywords, rather than methodological search terms.

Four search strings were developed: Cancer; Personality and Illness Beliefs;

Appraisal and Emotions; and Psychosocial Outcome (Table 2.1). Inclusion of terms into each search string was determined by both theory (based on personality theory and the Transactional Model) and the overall thesis aims. For example, although a plethora of different personality terms exist, and indeed were to be included in the review, the primary model of trait personality was the Five Factor theory. Therefore, although search strings included general personality terms, additional terms specific to this model were also included. Similarly, for cognitive appraisals and emotions, although general terms were included, terms highly specific to the Smith and Lazarus's Appraisal Components and Emotion Themes Questionnaires (1993) were also included.

Systematic review searches require careful consideration to ensure that the balance between sensitivity or recall, the chance of finding the majority of relevant literature, is maximised without loosing feasible levels of specificity or precision, making the search unfeasibly large and unfocussed. The crucial factor here is that too specific searching can often result in low sensitivity.

Table 2.1. Terms used in the development o f search strings.

Cancer Personality / Illness Beliefs Appraisal and Emotion Outcome

Oncology Personality Appraisal Quality of life

Neoplasm Neuroticism Attribution Mental adjustment

Cancer Pessimism Emotion Emotional adjustment

Carcinoma Optimism Shame Life change

Tum our Life Orientation Test Hum iliation Life Satisfaction

Sarcoma Hope Interest Anxiety

Malignant Positivism Surprise Depression

Adenocarcinoma Generalised Self-efficacy Boredom W ell being

Metastatic Five Factor Inventory Detachment Fatalism

Lymphoma Big Five Tranquillity Hopelessness

Myeloma Individual differences Relief Helplessness

Leukaemia Personality theory Anger Fighting spirit

Teratoma Extroversion Frustration Cognitive avoidance

Seminoma Introversion Resignation Anxious preoccupation

Teratocarcinoma Openness Guilt HADS

Melanoma Agreeableness Fear FACT Inventory

Adenoma Conscientiousness Sadness MAC Inventory

Choriocarcinoma NEO Inventory Hope MiniMAC

Glioma Helplessness Challenge

Astrocytoma Hoplessness Happiness

Blastoma Expectations Coping

(non-) Hodkins Cognitive style Core relational themes

Craniopharyngioma Intern al/extern al Relational meaning

Ependymoma Locus of Control Emotion theme

Esthesioneuroblastoma Transactional

Fibrosarcoma Lazarus

Lymphangioma Porocarcinoma Oliogodendroglioma Osteosarcoma Nephroblastoma

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Early scoping searches highlighted that this literature was vast and that there was little consistency between use of theoretical definitions (see also section

3.6.3). Therefore, in order to minimise the number of studies which may

otherwise have been missed by a specific and focused search, a high frequency of search terms were used. Sensitivity was thereby maximised, albeit by increasing the total recall rate and reducing search precision. Programming commands and Boolean operators were then applied to each term, and translated for each

database, to enable accurate searching of different spellings or truncations of terms.

Once terms were established, each was translated into an appropriate Subject Heading (for the psychologically based databases) or a MeSH Heading (a thesaurus based hierarchy developed by the National Library of Medicine used for the medically oriented databases) (Higgins & Green, 2005). Essentially, Subject Headings and MeSH Headings are equivalent; they are general terms or keywords used to describe each piece of published research held in a database, organised into a theoretical hierarchy of terms with links to 'narrower' (related, but more focused), terms. To demonstrate this complex organisation priniciple, figure 2.1 shows a hierarchy for both PsychlNFO and MEDLINE when searching for the concept of personality.

By identifying and 'exploding' key terms, researchers are able to quickly and accurately identify any piece of research held on the database whose subject heading fits into any term in the hierarchy at, or below the level of the specific term entered. This search method further enables high sensitivity searching and is encouraged by both Cochrane guidance and the NHSCRD.

Search strings were then combined into three combinations, one for each of the questions described in this chapter overview:

• 'Cancer' and 'Personality' and 'Appraisals and Emotions'

• 'Cancer' and 'Personality' and 'Outcome'

• 'Cancer' and 'Appraisals and Emotions' and 'Outcome'.

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PsychlNFO MEDLINE

Personality 4816 Psychiatry

v* Used For Behaviour & behavioural mechanisms 0

Character ^{< -*•} Adapation, Psychological 24595

Disposition Attitude 8672

Temperament Behaviour 4792

v* Narrower Terms ^{V * .} Child rearing 863

Inadequate personality 2 *-► Defense mechanisms 1849

Personality traits [+nt] 8243 Emotions 9226

Psychoanalytic 132 Human characteristics 164

personality factors

Related terms Human development 758

Cognitive Style (♦nt) 1677 Mental competency 2950

v -fr

Coronary prone behaviour 218 Motivation 13642

Egocentrism 175 Neurobehavioral manifestations 127

V * .

Emotional adjustment 3217 Personality 4891

[♦nt]

v * Emotional states [♦nt] 6829 Assertiveness 373

Five factor personality model

919 Authoritarianism 349

*-► Gender identity [+nt] 1784 ^{V *} Character 415

Human nature 861 ^{V *} Creativeness 1465

Individual differences 5076 Dependency

(psychology)

427

Lifestyle [♦nt] 1431 ^«-► Empathy 4494

»-► Person environment fit 397 ^W Individuality 2779

Personality change 389 Intelligence 4381

V * .

Personality correlates 846 ^W Leadership 10236

Personality development

Personality theory [+nt] 1438 Temperament 1461

Predisposition 515 Psychology,

Social

899

»-► Psychodynamics 3003 Behaviour discipline and activities 0

Self actualization 274 Mental disorders 29783

Self concept [♦nt] 7893 Psychological phenomena and 0

processes

*-► Self evaluation 1494 Biological Sciences

V * Self monitoring (personality)

145

V * Self perception 3459

w Somatotypes 32

Teacher personality 50

Note: In PsychlNFO, personality is the highest term in its appropriate Subject Heading Tree, however, in MEDLINE, personality appears as a narrower term under a higher MeSH Heading. Numbers refer to the number o f article links fo r each term. [+nt] indicates that specific terms have hierarchical trees of their own which, if exploded, would all be included.

Figure 2.1. Search term hierarchies in PsychlNFO and MEDLINE.

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2.4.1.2 Search strategy

As the subject of psychosocial oncology is multi-disciplinary, a wide range of electronic databases were used in literature searching spanning the fields of medicine, psychology, nursing and complementary health. The chosen databases represent international literature searching, including searching of the grey literature:

• Allied & Complementary Medicine Database (AMED)

• British Nursing Index (BNI)

• Cochrane Central Register of Controlled Trials (CENTRAL)

• Cochrane Database of Systematic Reviews

• Cumulative Index to Nursing and Allied Health Literature (CINAHL)

• Database of Abstracts of Review of Effects (DARE) EMBASE

• Health Management Information Consortium (HMIC)

• Health Technology Assessment Database (HTA) MEDLINE

• PsychlNFO

• Social Science Citation Index (SSCI)

• System of Information on Grey Literature in Europe (SIGLE) Systematic reviews often include searches of health service research registers (for example, the National Research Register or the Current Science Register of Controlled Trials); hand searching of conference abstracts from relevant professional societies; and/or, an email request to the key researchers within the field. Egger et al. (2001), for example, claim that only 50% of

conference abstracts, and even fewer dissertations (around 30%), are ever

published, therefore, searches purely limited to the published literature may miss relevant data. Typically though, unpublished studies are lower in methodological quality; inclusion, therefore, carries potential to introduce methodological bias into the review. The observation that publication of negative results is often much harder to achieve (therefore potentially biasing the direction of mean effect sizes in a statistical meta-analysis) further confuses matters on this issue.

Searching for non-published data can dramatically increase the length of time required to complete a review and is not always feasible. Whilst it is

acknowledged that to include searching of non-published works could have

introduced extra information, due to the ongoing debate regarding their suitability, and for practical reasons relating to the time allocation for this part of the thesis, literature searching for this review focused on published literature only.

In document Systematic review and empirical investigation of adjustment to cancer diagnosis: Predicting clinically relevant psychosocial outcomes and testing Lazarus's Transactional Model of stress (Page 60-65)