Table 3 Advantages, limitations and considerations of several study design options

Single center versus multicenter

Single center studies provide information on one’s own performance which is needed to induce a quality improvement cycle

For scientific purposes it is easier to identify which results can be extrapolated to other institutes when the results are obtained via a multicenter study. Furthermore, in a multicenter study benchmarking between the centers is possible.

Compare the results with the current literature on the preventability of readmissions, and be aware of (inter)national and regional differences in organization of care.

Population

(Focus on a specific population versus a broad population)

Manual review is easier to perform on a specific group (e.g. diagnosis heart failure or department).

Focus on single group can cause underestimation of the preventability readmission rate and/or underreporting of certain causes.

Consider a multidisciplinary panel or team to review the readmissions to reduce blind spots.

Relatedness (focus on readmissions that are related to the index readmission versus all-cause readmissions)

Readmissions related to the index hospitalization will generally identify causes that are related to hospital care.

All-cause readmissions are easier to identify based on administrative data, provide a broad scope and will identify other causes; for example causes related to care in the primary care setting.

Determine the scope of the quality improvement cycle; to identify causes related to hospital care or to care of a region

Type of readmissions

(unplanned versus planned readmissions)

Selecting only unplanned readmissions resembles the readmissions that are used to calculate the readmission quality indicator

Planned readmission might also have preventable causes which will be missed if planned readmissions are excluded

Determine whether you consider unplanned readmissions preventable prior to starting a readmission study

Setting and sources

(focus on hospital versus an integrated care network)

Assessment based on a hospital’s perspective only requires the medical record as single source.

Fragmented and incomplete description of the patient’s journey can result in underreporting causes related to integrated care, patient and social factors.

Interview, questionnaire or survey a (subset) of patients and or primary care providers.

Information and sources

(which sources and information to include; and in which order)

Including the full medical record, outpatient data and even additional sources (e.g. interviews) can change the perspective on preventability and its causes.

Reviewers might use a different approach of obtaining/using the (additional) information which can create unwanted differences in the perspective on preventability.

Note that for an interview of stakeholders a cross-sectional or prospective study design is needed to reduce recall bias.

A strict protocol and logbook as well as training prior to start of the study. Consider to provide additional information stepwise to assess its added value on the preventability assessment.

A priori (preventability) cause classification

Easier to perform and probably better agreement between reviewers.

Does not invite reviewer to look beyond this list of predefined (potentially preventable) causes and can therefore narrow the reviewer’s view.

Usa a multidisciplinary approach with more than one reviewer. The use of a strict protocol and logbook as well as training prior to start of the study, and case discussion during the study, can increase uniformity

Reviewers

(single reviewer

versus duo/team)

Using a single reviewer to perform the preventability assessment is less time-consuming.

Due to the poor reproducibility some kind of double check is needed.

Double (partial) review can increase uniformity. If a double check is not possible, consider a team or panel discussion (of a subset) of cases. Moreover, case discussion adds to the learning and awareness component of the medical record review process.

Experience

Residents as reviewer can contribute to the learning environment.

Some studies suggest that years of experience can influence the preventability assessment.

Approach seniors to be available for supervision, double check by a senior and/or training, strict protocol or discussion meetings.

Complete or partial double check

A partial double check is less time consuming.

This can influence the agreement calculation.

In case of partial double check use the appropriate analysis.

Final preventability judgment

(binary score versus scale or category)

Using a binary score for preventability is straightforward and easy to interpret

Since the majority of readmissions have multifactorial causes a binary preventability score does not resemble reality; a scale of category offers the option of making a thoughtful decision

Use a scale or category which includes intermediate scores on preventability. Be clear on which categories are used/combined to calculate the preventability percentage.