Table 3 Summary of interventional studies

Song et al., 2010 [31] (USA)

To determine whether homeless persons will complete a counselling session on ACP with a social worker and fill out a legal AD.

A single-blind, randomized controlled trial

Homeless persons recruited from 8 sites were randomly assigned to one of 2 groups: a self-guided intervention and a counselor-guided intervention

1. The overall completion rate for ADs was significantly higher in the one-to-one counselling group than in the self-guided group (37.9% vs. 12.8%).

2. This difference persisted across all of the eight sites and most subgroups.

Johnson & Stadel, 2007 [27] (USA)

To test the efficacy of a preadmission educational interview by a social worker on the completion of Ads

A quasi-experimental study

Adult orthopedic surgical patients who were admitted to a hospital for hip or knee replacement surgery

1. After the intervention, 43% of patients in the treatment group had a health care proxy on their charts, compared to 6% of those in the comparison group (p < .005).

2. Age, residence, ethnicity, and diagnosis were found not to have significant impact on signing a health care proxy.

Pearlman et al., 2005 [28] (USA)

To increase ACP use through an educational and motivational intervention by social workers.

A randomized controlled clinical trial

A sample of veteran patients recruited from 23 providers were randomized into the intervention or control group.

1. Compared to the controls, the intervention patients reported more ACP discussions with their providers (64% vs 38%). Living wills were filed in the medical record twice as often in the intervention group (48% vs 23%).

2. Provider-patient dyads in the intervention group had higher agreement scores than the control group for treatment preferences, values, and personal beliefs (p < .01).

Morrison et al., 2005 [29] (USA)

To assess the effect of a ACP intervention directed at social workers on identification and documentation of preferences for medical treatments and on patient outcomes

A randomized controlled trial

Newly admitted long-term care residents were allocated into either an intervention or a control group.

1. Intervention residents were significantly more likely than residents in the control group to have their preferences regarding cardiopulmonary resuscitation (p = .005), artificial nutrition and hydration (p < .01), intravenous antibiotics (p < .01), and hospitalization (p < .01) documented in the nursing home chart.

2. Control residents were significantly more likely than intervention residents to receive treatments discordant with their prior stated wishes.

Dipko et al., 2003 [32] (USA)

To examine the effectiveness of group education sessions in increasing completion of ADs

A retrospective cohort control study

A cohort of outpatients was divided into three categories: group participants, individually educated patients, and the patients with no AD education.

1. Social work education of any kind resulted in an overall completion rate of 20% versus 2.1% in the non-intervention group.

2. Group education was twice as effective as an individual social work session, and as effective as multiple sessions, but less time consuming.

Gockel et al., 1998 [30] (USA)

To evaluate the effect of an educational intervention by social workers on the completion of ADs

An uncontrolled observational study

A convenient sample of outpatients recruited at an ambulatory care setting

1. An educational intervention increases the percentage of individuals who initiate an AD.

2. Patients with more hospitalizations were more likely not to have an AD.

Bailly & DePoy, 1995 [33] (USA)

To evaluate a social work program designed to promote older people’s autonomous decision making regarding ADs.

An uncontrolled observational study

A convenient sample of older clients who regularly used family medical care services.

1. The results revealed a continuum of willingness among elderly people to address future decision making.

Luptak & Boult, 1994 [34] (USA)

To examine the effectiveness of an intervention implemented by a social worker to help frail elders to record AD

An uncontrolled observational study

All patients who visited an experimental geriatric evaluation and management clinic during a period of 14 months.

1. 71% of the participants recorded AD. Of these, 96% named a proxy and 83% recorded specific treatment preferences.