Evidence-Based Practice for Nurses

questionnaire/survey is important, along with providing them contact informa-

tion if they have additional questions/concerns (Meadows, 2003).

Observation

Structured observations provide a way to quantify an explicit feature of the

phenomenon under observation. For example, a researcher could count the

number of people who wash their hands after using a public restroom. Research-

ers serve as objective observers and follow systematic methods using specific

directions during a scheduled period of time. In the hand washing example, the

researcher may observe individuals during dinner time at a popular restaurant.

Not only do researchers outline what observations are made but they also note

how observations are recorded and coded. The researcher in this example may

record tallies under three columns: no hand washing, water only, or soap and

water. Establishing a detailed protocol is extremely important if researchers

use research assistants.

Scales

Scales are used to assign a numeric value or score along a continuum. They

are frequently incorporated into a questionnaire or interview. Numerous

types of scales have been developed to measure social and psychological

concepts specific to nursing. Researchers choose scales based on the scales’

ability to measure identified concepts. Ideally, it is best to choose scales that

have already been tested. If a scale does not exist, researchers can develop

and test a new scale (Meadows, 2003). Scales can be designed to measure

either a single or multidimensional concept. For example, the Marwit-Meuser

Caregiver Grief Inventory is a 50-item multidimensional scale that measures

grief reactions by current caregivers of people with progressive dementias

(Marwit & Meuser, 2002). Because three subscales compose the total grief

score, it is a multidimensional scale. Each subscale measures a specific part of

the caregiving experience as detailed in the Caregiver Grief Model (Meuser &

Marwit, 2001).

You may already be familiar with Likert scales, which are frequently used to

collect data. A Likert scale consists of statements placed on a continuum of seven

points and to which respondents indicate whether they agree or disagree. Seven

points allow for a neutral opinion. Some researchers find a neutral response

hard to interpret. Therefore, researchers may adapt the scale to eliminate the

neutral point by having an even number of points. Scales containing fewer than

seven points are known as Likert-type scales (see Figure 10-2).

Another type of scale is the visual analog scale (VAS) (see Figure 10-3).

Researchers use this type of scale to measure the intensity of sensations and

KEY TERMS

observation: A

technique to

gather data

scales: Used to

assign a numeric

value or score a

continuum

Likert scales:

Ordinal-level

scales containing

seven points on an

agree or disagree

continuum

visual analog scale

(VAS): Ratio-level

scale of a 100-mm

line anchored on

each end with

words or symbols

258 CHAPTER 10 Collecting Evidence