JCPSLP Vol 23, Issue 1 2021

Table 2. Key methodological features and findings from reviewed studies of quantitative studies

Author

Study design

Participants

DMCA tools Findings

Cross-sectional (online survey)

(n = 59) speech pathologists

MacCAT-T

• 86.4% SLP has been involved in DMCA • Increased confidence was correlated with greater clinical experience • Formal DMC guidelines would increase SLP confidence • Treating physicians found lower rates of incapacity as compared with test results • There was poor concordance between the investigator’s judgment and treating physicians • DMC was overestimated by all clinicians • Influence of values and beliefs and their impact on bias • Decisions made by patients without capacity is a major ethical issue and places the patient at risk of inappropriate treatment and abuse • MMSE & ACE together are a reliable assessment of DMC • Up to 50% of patients with brain metastasis has impaired understanding • Tests of short-term memory, executive function, and processing speed were predictive of a patient’s understanding • DMC of terminally ill patients was more impaired than healthy controls • Poor agreement between physician rated DMC and performance on assessment • 85.7% of terminally ill patients could express a treatment decision • 44.2% had some level of impairment in understanding and appreciation scales. 85.4% had difficulty with reasoning scales. • 90% were impaired on at least one section of the test • linicians have reduced knowledge about DMC • Greater education, governance, and legal knowledge are required • Reduced memory and attention demands can assist people with dementia in the DMCA process • Supportive communication strategies are required to support people with dementia engage in decision- making • Physicians should receive appropriate communication training • Red flags for impaired DMC should be clear • DMCA needs to form part of health policy • Understanding is the most cognitively taxing component of DMCA • Patients with brain metastasis more impaired on reasoning and understanding over 50% had some form of DMC impairment 50% had impaired understanding and 40% impaired reasoning • Many physicians had low knowledge about clinical and legal aspects of a DMCA • 30% of hospital physicians and 24% GPs reported DMCA was not within scope of practice • Physician training is required

Aldous et al., 2014 Australia

Bilanakis et al., 2014 Greece

(n = 78) consecutive admissions to hospital

MacCaT-T (Greek) MMSE

Consecutive cohort study analytic + experimental study design with blinding

Bertrand et al., 2019 France

MMSE ACE

Prevalence study

(n = 206) patients (n = 213) consultants, nurses and registrars

(n = 41) patients with brain metastasis (n = 41) controls

Case-control group (comparison group) with blinding

Gerstenecker et al., 2015 USA

CCTI

MacCAT-T

Kolva et al., 2018 USA

(n = 55) palliative care in patients with

Case-control convenience sample comparison group

terminal cancer (n = 50) healthy

controls demographic similarities (n = 105)

Lamont et al., 2019 Australia

(n = 86) clinicians (n = 24) exited after the first question

Nil

An exploratory descriptive cross- sectional survey

Mueller et al., 2017 Germany

Case-control study

(n = 53) people with mild to moderate dementia (n = 133)

MacCAT-T (an adapted version of the German tool)

no cognitive impairment

Triebel et al., 2015 USA

Case-control study

(n = 41) patients with brain metastasis (n = 41) controls

CCTI

Nil

Young et al., 2018 New Zealand

Convenience sample of (n = 152) hospital doctors and (n = 74) general practitioners (GP)

Mixed methods case-control and cross-sectional study (survey)

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JCPSLP Volume 23, Number 1 2021

Journal of Clinical Practice in Speech-Language Pathology