Table 2 Description and results of the studies on automated dose dispensing (ADD) in primary healthcare

Controlled studies

Sjöberg et al.[15], 2012, Sweden

To compare changes in drug treatments within and outside ADD

Level 2

154 community-dwelling or nursing home residents ≥65 years of age (patients using ADD n = 107, not using ADD n = 47). Data on drug treatments were extracted from the medical records (t = 0 months) and from the SPDR (t = 6 months). A multi-level analysis was performed, with drugs at the first level and individuals at the second.

Number of changed (withdrawn, dosage adjusted, or newly prescribed) and not changed drugs.

Appropriateness of medication use

Controlled register study

The risk of medication to be classified as unchanged was higher among ADD users (OR 1.66, 95% CI 1.20-2.31, adjusted for age, sex, cognition, year of data collection, subgroup of drug).

Sjöberg et al.[16], 2011, Sweden

To investigate association between ADD and quality of drug treatment

Level 3

All community-dwelling or nursing home residents from Västra Götaland ≥65 years of age in late 2007 and having ≥2 health care visits and ≥2 diagnosis in 2005–2007. Study group: ADD users (n = 4927). Control group: patients not using ADD (n = 19 219). Data were collected from the SPDR in 2007 linked with register data on patient diagnoses and residence.

Five quality indicators for potential IDU:

Appropriateness of medication use

Controlled cross-sectional register study

1. Use of ≥10 drugs

ADD users had a higher prevalence of all indicators of potential IDU (5.9-55.1%) than the control population (2.6-4.9%) (P <0.0001). After adjustment for age, sex, burden of disease, and residence, risk of all indicators of potential IDU were higher among ADD users (ORs 1.36-5.48; 95% CI 1.18-6.30).

2. Use of long-acting benzodiazepines

3. Use of anticholinergic drugs

4. Use of ≥3 psychotropic drugs

5. Potential DDIs

Wekre et al.[17], 2010, Norway

Impact of ADD on inconsistencies in medication records between GPs and home care services

Level 3

A convenience sample of 59 patients. Medication records were collected 0.5 years before and 1 year after the ADD implementation.

Number of discrepancies between the patients’ medication records at the GPs and at the home care services

Medication safety

ADD did not change the number of medication records with discrepancies (before 47 and after 45 out of 59, P = 0.774, n.s.), but reduced total number of discrepancies by 34% (P < 0.001).

Controlled before-after study

Johnell and Fastbom[18], 2008, Sweden

Whether the use of ADD is associated with potential IDU

Level 2

All Swedes ≥75 years of age who were registered in SPDR. Study group: ADD users (n = 122 413). Control group: patients not using ADD (n = 608, 692). Data were collected from the SPDR in 2005.

Four quality indicators for potential IDU:

Appropriateness of medication use

ADD users had a higher prevalence of all indicators of potential IDU (8.8-22.1%) than the control population (2.4-4.9%).

Controlled cross-sectional register study

1. use of long-acting benzodiazepines

2. use of anticholinergic drugs

After adjustment for age and number of dispensed drugs, risk of using any IDU, anticholinergic drugs and ≥3 psychotropic drugs were higher among ADD users (ORs 1.43-4.93; 95% CI 1.40-5.17). Contrasting relationship prevailed for long-acting benzodiazepines among women and potentially serious DDIs among women and men (ORs 0.69-0.80; 95% CI 0.66-0.83).

3. use of ≥3 psychotropic drugs

4. potential DDIs

Uncontrolled studies

Olsson et al.[19], 2010, Sweden

Extent and quality of drug prescribing in younger elderly (65–79 years) and older elderly (≥80 years) receiving ADD

ADD is mentioned but no description is given.

All residents of nursing homes and dementia special care units ≥65 years of age (n = 3705) from the County of Jönköping. Data on prescribed drugs were collected from the national pharmacy drug register.

Five quality indicators for potential IDU:

Appropriateness of medication use

Cross-sectional register study

1. Use of long-acting benzodiazepines

Influence of ADD on potential IDU not studied. Potential IDU prevalences ranged from 7.6% to 41.2%. Prevalences of potential IDU were mainly higher among younger (65–79 years) than older (≥80 years) residents (not statistically tested).

2. Use of anticholinergic drugs

3. drug duplications

4. Use of ≥3 psychotropic drugs

5. Potential DDIs

van den Bemt et al.[20], 2009, the Netherlands

Frequency of medication administration errors and potential risk factors for these errors in nursing homes using ADD

Level 2

In all, 2025 administrations to 127 residents of three nursing homes were observed by one pharmacy technician.

Medication administration error rates

Medication safety

Administration error rate for all administered medications observed (via ADD and without ADD) was 21.2% (n = 428 errors). Most common error type was wrong administration technique (n = 312). The risk for administration errors was higher when medicine was not supplied by ADD (OR 2.92; 95% CI 2.04-4.18).

Prospective observational study

Bergman et al.[21], 2007, Sweden

Quality of drug therapy among nursing home residents using ADD

Level 1

All nursing home residents ≥65 years of age (n = 7904) from Gothenburg area. Data were collected from the Swedish national drug register for ADD users.

Five quality indicators for potential IDU:

Appropriateness of medication use

Cross-sectional register study

1. use of long-acting benzodiazepines

Influence of ADD on potential IDU not studied. Potential IDU prevalences ranged from 12.1% to 45.2%. The proportion of potential IDU was higher among 65–79 year-old residents than those ≥80 years old (P 0.001-0.015).

2. Use of anticholinergic drugs

3. Drug duplications

4. Use of ≥3 psychotropic drugs

5. Potential DDIs