Achieved Study Samples

The required sample for each Phase of the study was achieved by means of the previously described inclusion and exclusion criteria and the recruitment procedure. The first and third Phase of the study utilised a reference group of seven clinicians within a neonatal transport team. Phase Two of the study utilised purposive

homogenous sampling.

This is a non-random method of sampling, aimed at sampling a group with a particular characteristic. It is also called judgement sampling, as respondents are selected due to their specific knowledge which is valuable to the research (Bowling 2004). The achieved sample sizes for each Phase of the study can be reviewed below in Figure 20.

Figure 20 Achieved Samples for Each Phase of the Study

4.14.1

Confidentiality

Participants have the right to expect that their data will be kept and applied in the strictest confidence. Anonymity is rarely possible in qualitative studies as the researcher frequently interacts with the participant in the form of interviews or focus group meetings. In relation to the Delphi Phase of the study, the issue of anonymity can present problems. Complete anonymity during a Delphi cannot always be guaranteed due to the fact that the researcher will provide feedback to the participants.

Phase One - Nominal Group Technique Reference Group: 7 transport clinicians

No refusals

Phase Two- Delphi Study- Purposive homogenous sample 2 round questionnaire:

Round 1- 102 participants

Round 2- 49 participants, 48% of initial panel

Phase Three- Conversational Semi-structured interviews Reference group: 7 transport clinicians

However the researcher can ensure that responses cannot be attributed to any individual panel member by the group (Keeney et al. 2011). Therefore maintaining the rights and anonymity of the participants were addressed by various means throughout the study.

This included informed consent and the following measures:

● Sensitivity to cultural and linguistic diversity

● Questions phrased tactfully, presented in a polite sensitive manner ● Transparency of consent procedures

● Emphasise the participants’ right to withdraw at any time ● Ensuring balance between paternalism and autonomy ● Awareness of the risk of manipulation or coercion ● Ensuring anonymity in the final written report ● Continued assessment of vulnerability

● Study data/materials are locked in a secure location and electronic data password protected, and data destroyed within the accepted timeframe

4.14.2

Limitations of the Methods

This section of the Chapter will address issues relating to rigour which correspond to the robustness and integrity of the research design. Within the context of this study consideration has been given to those elements ensuring validity (Polit and Beck 2010),reliability (Bryman 2008) generalizability (Yin 2009) and objectivity (Parahoo 2006, Denscombe 2007). Therefore by highlighting the potential

limitations associated with the study methods, the following methods were utilised to increase confidence in findings.

4.14.3

Validity (Credibility)

The validity of the study is an important reflection of the trustworthiness of the findings (Yin 2009, Polit and Beck 2010). The validity or credibility refers to the:

“ability of the instrument to measure the attributes of the construct under study”

(De Von et al. 2007 p155)

Validity is divided into external, which is an indication of generalizability of the findings and internal which refers to the confidence placed on the cause and effect relationship.

-

Content Validity

There are several ways in which validity can be measured, these include content and criterion- related. In relation to content validity De Von et al. (2007 p155) states that it estimates if:

“the item in the tool sample the complete range of the attribute under study”.

It is reported by several authors that Delphi provides evidence of content and face validity (Sharkey and Sharples 2001, Morgan et al. 2007, Huang et al. 2008), this view is linked to the structure of the Delphi which is based on group opinion rather than an individual which is deemed to be more valid. Also both the Delphi process and NGT within this study is generated from expert opinion which provides confirmative judgements (Cross 1999, Spencer-Cooke 1989). This is also strengthened by the fact that the Delphi process within this study has a qualitative first round in the NGT which generates scale items from an expert group with the ability to review and judge the appropriateness of the scale through the consecutive Delphi rounds.

- Criterion-related Validity

There are two types of criterion-related validity: concurrent and predictive. Concurrent validity can be demonstrated when a test is correlated with a measure that has been previously validated.

Criterion-related validity is established when:

“a test is shown to be effective in predicting criterion or indicators of a construct”.

De Von et al. (2007 p100).

However predictive validity is where one measure occurs earlier and is meant to predict a later measure (McIntire and Miller 2005). The Delphi process contributes to concurrent validity due to the successive rounds (Sharkey and Sharples 2001, Hasson et al. 2000) and also by achieving consensus from the expert panel, which is demonstrated in both the Delphi and NGT. However predictive validity is frequently measured in terms of accuracy, which is often viewed as evidence of validity (Keeney et al. 2011, Streiner and Norman 1995).

There are however challenges in establishing external and internal validity in any study, generalising results to the wider population may be inappropriate if the study was

undertaken with a specific sample at a specific time. The Delphi and NGT experts may not be typical of the general population (Keeney et al. 2011), however it can be argued that neonatal transport is a specialised specific population.

4.14.4

Factors which may Influence Validity

There are a variety of influencing factors which can present a threat to the validity of consensus methods. These include:

- The Sample

The selected sample may have certain characteristics which may influence results. It has been highlighted that validity is affected by the number of experts, the extent of expertise and the level of consensus (Rowe et al. 1991). Furthermore due to the difference in

backgrounds and experience within a panel results may not be replicated in another group of similarly qualified individuals (Sandrey and Bulger 2008).

In the Delphi process due to anonymity there may be a lack of accountability in responses from panel members which can influence results (Simoens 2006). Alternatively in a small panel members may be aware of other panel member identity and this potentially could sway the arguments by others discounting their views.

- Modified Techniques

It has been argued that the various modifications to the Delphi process threaten the validity and reliability of the process (McKenna and Keeney 2008). This can refer to various aspects of the Delphi method including number of rounds, timing and lack of consensus. However it has to be acknowledged that successive Delphi rounds may lead to fatigue which can affect response rates, panel members may drop out before the end of the process which may affect results (Simoens 2006).

- Researcher Bias

As the researcher is responsible for ensuring that the content is manageable and in the Delphi process there is no opportunity to engage with participants, the risk of researcher bias is always a potential risk (Walker and Selfie 1996, Sumison 1998).

Most Delphi studies use an open qualitative first round which then is reduced by utilising content reviews, this then informs the remainder of the Delphi process. However it has been argued that many Delphi studies have not fully addressed issues of validity (Rowe et al. 1991). As each Delphi study is unique it is unclear how these issues should be

established (Engles and Kennedy 2007). It has been suggested that additional research to validate findings could be undertaken (Engles and Kennedy 2007, Van Dijk 1990). This may be in the form of pilot studies with special interest group members (Van Zolingen and Klaasen 2003) or face to face interviews prior to commencement of the Delphi (Delbecq et al. 1975).

However in response to claims criticising reliability of consensus methods such as Delphi, it was recommended that establishing guidelines by which the quality of the method can be tested would facilitate reliability. These would include:

∙ Applying the method to a specific problem

∙ Appropriate selection of respondents and their expertise ∙ Design and administration

∙ Feedback ∙ Consensus ∙ Group Meeting