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eTriage had already been introduced as an intervention to support increased demand and mitigate against threats to quality and safety that increased activity and inexperience may produce. A quantitative method had already been identified as the most appropriate means by which to answer the research question. Once a quantitative approach was deemed the most suitable to answer the research question the search for a robust design began. A quasi-experimental design was selected after careful consideration of alternative quantitative designs identified by EPOC (2013b), namely a randomised controlled trial (RCT), a non- randomised controlled trial (NRCT) and a controlled before and after study (CBA). 4.5.1 Randomised controlled trials

RCTs are often viewed as the gold standard design for studies investigating cause and effect (Polit & Beck, 2008). They are often not possible in biomedical informatics research due to the challenges of randomising and blinding participants and researchers (Friedman & Wyatt, 2010). The comprehensive series of six systematic reviews on CCDSSs published by Hemens et al (2011), Nieuwlaat et al (2011), Roshanov et al (2011a), Roshanov et al (2011b), Sahota et

al (2011) and Souza et al (2011) chose to include only RCTs (Haynes & Wilczynski, 2010). Whilst RCTs have been used in the study of CCDSSs in acute care (Sahota et al., 2011) only 4/36 (11%) studies included in the acute care systematic review were undertaken in an ED (Gonzalez, Vanderheyden, Ornato , & Comstock, 1989; Wyatt, J, 1989; Roukema et al., 2008; Terrell et al., 2009). Two provided guidance on drug dosing in a specific clinical situations; asthma and in older people respectively (Gonzalez et al., 1989; Terrell et al., 2009). The other two studies suggested actions in single discrete clinical situations; chest pain (Wyatt, J, 1989) & clinical investigations for children at high risk of serious bacterial infection (Roukema et al., 2008).

Within the more recent literature review for this thesis a further two RCTs were identified (Roy et al., 2009; Dexheimer et al., 2013). The studies by Wyatt (1989), Terrell et al (2009) and Gonzalez et al (1989) did not meet the inclusion criteria for the literature review in this thesis. Of the remaining three RCTs that were critically appraised, two had methodological weaknesses (Roukema et al., 2008; Dexheimer et al., 2013) and the cluster RCT by Roy et al (2009) whilst methodologically stronger was a very significant undertaking as it took place in 20 EDs across France. The maintenance of the internal validity of an RCT in the ED setting to evaluate the impact of CCDSSs is very challenging. Both the studies by Roukema et al (2008) and (Dexheimer et al., 2013) were not able to adequately control for the contamination that resulted from the clinician not being blinded to which arm of the trial the patient was in i.e. control or intervention.

For this study it was not be practical or feasible to randomise ED patients to a control group (usual triage) and an intervention group (eTriage). One of the strengths of this research is that it was conducted in clinical practice and evaluated the impact of the CCDSS in current use. Running two parallel triage systems (usual triage and eTriage) and then randomising patients to one or the other would not be workable in a busy ED. There would need to be two triage points: usual triage and eTriage. The patient would attend one or the other, depending on which they were randomised to. Alternatively a single triage nurse could alternate between systems depending on which one the patient was

randomised to. In both these scenarios blinding would be impossible and performance bias as well as the risk of contamination would have an unknown effect on the results (EPOC, 2013a).

An alternative approach could have been a two-centre study. Another ED that used the MTS could have been selected as the control. Randomised triage records could have been analysed from both departments. It would have proven more difficult to retrieve data regarding patients who presented with neutropenia from another hospital. Most EDs have unique processes for managing patient flow and acuity due to differing departmental geography and staffing levels. Some efforts were made to establish if a local department had similar characteristics to the ED in this study to reduce the impact of potential confounding factors. For example: similar geographical layout, cubicle space, staffing levels, triage training and level of   triage   nurses’   experience.   None   were   viewed   by   the   researcher   as   a   suitable   match.

Of equal importance to this study was the secondary outcome measure, which assessed the impact of eTriage on the management of patients with neutropenic sepsis. Comparing processes for that patient group in another ED would not be appropriate either for the reasons outlined above. It is also important to highlight that eTriage was a planned development within the ED, despite the research that was subsequently undertaken. Once a new process or system has been introduced, the use of an appropriate experimental design to evaluate it is more limited (Siriwardena, 2007).

Once the feasibility of undertaking a RCT was explored and rejected an assessment of other appropriate methods was necessary. A research method was required that could be administered in a busy ED with minimal disruption but that was robust enough to give an acceptable degree of confidence in its results. EPOC (2013b) recognise that RCTs are often not appropriate methods for research into interventions to improve health care delivery. The other study designs that are viewed as appropriate for inclusion in an EPOC systematic review, if they are conducted robustly are: NRCTs, CBA studies and ITS design (EPOC, 2013b). It is

with these criteria in mind that NRCTs, CBA studies and ITS design were also considered.

4.5.2 Non-randomised designs

When an intervention has already been introduced, as in the case of eTriage non- randomised methods (NRCT) or quasi-experimental designs (CBA studies, ITS design) are often an appropriate research option (Siriwardena, 2007). A NRCT has two study groups one exposed to the intervention, while the other acts as the control. The participants are allocated to either group by methods which are arbitrary (Cochrane Childhood Cancer Group, n.d.). In a NRCT the participants are opportunistically allocated to either the control or intervention group. Lack of randomisation   is   seen   as   a   significant   flaw   in   a   trial’s   design   as   it   introduces   potential bias (Higgins & Green, 2011). There may be naturally occurring differences between the groups e.g. age, gender, severity of illness and the process of non-random allocation itself creates selection bias (Higgins & Green, 2011). Matching subjects with similar characteristics can be undertaken to reduce bias. However, in a comprehensive study which compared the results of studies from randomised and non-randomised trials on the same intervention, differences were found (Deeks et al., 2003). There was an overall conclusion that an evidence-base may need re-examining if established through non-randomised designs (Deeks et al., 2003). In some clinical settings a NRCT may be more feasible than an RCT, however the impracticalities of running two different triage systems simultaneously regardless of whether the patients are randomised or not remain the same. Whilst it has been established that an RCT is not appropriate method for practical reasons, a NRCT was discounted as well due to the same practical reasons as well as its inherent bias.

4.5.3 Before and after studies

A CBA study is identified by EPOC (2013b) as an appropriate method for inclusion in their systematic reviews. However, in an ED setting the concurrent identification of an intervention and a control group that have the primary and secondary outcomes measured before and after the introduction of eTriage is

impossible. Within the literature review for this thesis no CBA studies were identified. ED patients are transient; the identification of a concurrent control group is not feasible. For this reason alone the use of a CBA study was dismissed. Although simpler, a B&A study is not viewed as suitable means of assessing the impact of an intervention to improve practice (EPOC, 2013b). Despite this they are the most predominant method used in CCDSS research (Liu & Wyatt, 2011). They are also the most common method identified in the literature review within this thesis. Thirteen B&A studies were included and significant threats to internal validity were identified by the use of this method (Asaro et al., 2006; Goergen et al., 2006; Jadav et al., 2009; Kwok et al., 2009; Niemi et al., 2009; Melnick et al., 2010; Carman et al., 2011; Drescher et al., 2011; Nelson, J et al., 2011; Raja et al., 2012; Bond et al., 2013; Britton et al., 2013; Jones, B. et al., 2013).

EPOC (2013b) dismiss the use of B&A studies due to their inherent risk of bias. In a B&A study  the  outcomes  of  interest  are  measured  “before”  the  introduction  of   the  CCDSS  and  “after”.  Any  changes  are  assumed  to  be  due  to  the  effects  of  the   CCDSS (Siriwardena, 2007). However, one-off measurements before and after an intervention do not take into account natural changes that occur, regression to the mean or the influence of other external factors such as newly trained triage nurses (Polit & Beck 2008). There are always changes to behaviours, performance and adherence to guidelines for example, that alter over time. In a B&A study the underlying trend that would naturally occur is not evident and spurious results and the phenomenon of regression to the mean can arise depending on when the measurements are taken. See Figures 4.1 & 4.2 below for diagrammatic representation of these issues.

Figure 4.1. Before and after study. On-off measurements will not show the effect immediately post intervention adapted from Bender (n.d )

Figure 4.2. Before and after study. One-off measurements will not show that the intervention has made no difference if the underlying trend is not visible adapted from Bender (n.d)

A simple B&A study taking a single set of measurements before and after the introduction of eTriage was rejected. Whilst appealing to many CCDSS researchers due to its relative ease there are several significant threats to internal validity that result from; selection bias, performance bias, detection bias, attrition bias,

reporting bias and regression to the mean (Robson et al., 2001; Higgins et al., 2011; Higgins & Green, 2011). The next sections will describe in more detail the research design adopted.

4.5.4 Interrupted time series designs

ITS design is a quasi-experimental approach that has been used in CCDSS research. It is particularly well-suited to assessing the effects of the introduction of an intervention (Polit & Beck, 2008). ITS design has been used to assess the impact of: the introduction of new guidelines (Sheldon et al., 2004), health education interventions (Michielutte, Shelton B., Paskett, Tatum , & Velez, 2000), an electronic health record on nursing activities (Dowding et al., 2012), a CCDSS for antibiotic prescribing (Buising et al., 2008) and changes to legislation (Hawton et al., 2009). In an ITS study, repeated measurements are taken before and after the introduction of an intervention (Belcher, 2001). Measurements can be taken from the whole population or a sample if the population is large (Polit & Beck, 2008).

The strength of a ITS design, over-and-above a B&A study is that it removes some of the difficulties associated with invalid results from one-off measurements taken at a single point before and a single point after. Collecting data at intervals over a longer period of time before and after the introduction of an intervention will reveal the underlying secular trend (Biglan, Ary , & Wagenaar, 2000). This allows for stronger conclusions to be drawn about the actual effect of the intervention over and above what would have happened regardless of its introduction (Siriwardena, 2007; Flodgren & Oddgard-Jensen, 2013). The main source of bias in an ITS design remains the external effects on the change over time. However this is mitigated to a significant degree by the collection of data at multiple time points and the fact that pre-intervention data acts as the control (Polit & Beck, 2008). An ITS design was an appropriate method for this research for several other reasons. It is eminently suited to the retrospective analysis of data (England, 2005). As this research had no funding associated with it, a cost- effective method was necessary. ITS design is an emerging method in CCDSS

research; five studies having been identified in the literature review (Day et al., 1995; Schriger et al., 1997; Schriger et al., 2000; Buising et al., 2008; Gibbs et al., 2012). Although the quality of all but one of these studies was relatively poor (Buising et al., 2008), there was an opportunity with this research to add to the small body of higher quality research using an ITS design. Finally an ITS study can identify trends that an RCT is unable to isolate e.g. the immediacy of changes, the timing of the changes and the sustainability of the changes over time. It is of particular interest in this study to determine if any immediate improvement due to the launch of a novel system is maintained in the long term.

Taking all these features and limitations of the various study designs into consideration, an ITS design was selected as the most suitable approach for this research. The preliminary statistical analysis described later in the chapter and reported in chapter 5 did compare the pre and post eTriage groups (in a similar way to a B&A study). If large effects are demonstrated this can provide convincing evidence of the effect of an intervention (Brown & Lilford, 2008) However, to improve the quality of the study and reduce bias time series analysis was undertaken to evaluate changes over time based on the methods used by Buising et al., (2008). ITS design cannot determine cause and effect in the same way that a true experiment can (Sheldon et al., 2004). However, it can establish if the intervention was associated with a sustainable statistically significant change. 4.6 Research design

This next section will outline the complete design of the study and describe the setting, the samples used for the ITS and the data collection methods. The internal validity and the methods used to address confounding variables are described. The approach to and results of the inter-rater reliability testing will be explained. Finally the data analysis using SPSS (20.0) will be described and justified.

4.7 Setting

This research evaluated the triage decisions made in a district general hospital emergency department in the north of England. The department had used the MTS as its triage method since 1998. The pre eTriage data collection period ran from April 2009-January 2010; the post eTriage data collection period ran from April 2011-January 2012. The department covered a large urban and rural catchment area and saw a 2.6% increase in attendances during 2009-2011. Interestingly there was a significant increase in annual attendances in 2012 by a further 5.5%. The overall increase in attendances between 2009-2012 was 8.2%; 83,266 attendances in 2009 and 90,081 in 2012 (HSCIC, n.d.) The ED was situated in a large town with a population of approximately 300,000. Access to emergency or urgent health care for residents was via their own GP, an out-of-hours provider when their GP surgery was closed or by attending the ED. During the study period, a walk-in centre opened in October 2009, providing an alternative for patients with minor complaints, but closed in September 2010 as ED attendances continued to rise during the time rather than decline as was originally hoped. Most large towns and cities have alternatives to ED in the form of walk-in centres and minor injury units. They are either co-located with EDs or on a separate site, usually in the town/city centre. The provision of out-of-hours urgent and emergency care is somewhat unique in this locality as there were no alternatives as outlined above.

It   is   commonplace   in   most   UK   EDs   for   patients   to   arrive   by   one   of   two   ‘doors’.   Patients that are brought in by ambulance arrive via an ambulance entrance. Patients that  “walk-in”  are  those  that  have  travelled  by  any  other  means  and  they   have a separate entrance. In the case of this ED the walk-in entrance led into a waiting room with a large reception desk. All newly arrived patients were registered as an attendance into   the   hospital’s   patient   administration system (PAS). Once registered, patients waited for assessment by a triage nurse. There were two separate triage points   depending   on   the   patients’ mode of arrival: ambulance  triage  and  “walk-in”  triage.  Patients  who arrived by ambulance were triaged in a different physical location from those who walked-in. A small subset

of patients attending this ED did not undergo a triage assessment as they were assessed by a clinician on or shortly after arrival. This group of patients broadly fell into two categories. For a small number of critically ill or injured patients the ED   receives   a   “stand-by”   telephone   call   from   the   ambulance   service. A clinical team meets the patient as they arrive and treatment begins immediately, therefore negating the need to for a triage assessment. During periods of reduced activity, usually between 05:00-09:00hrs clinicians might be ready to assess patients at they arrive - again negating the need for triage. The researcher for this study is a Senior Nurse working in the ED with a joint clinical and service/staff development role. The ED staff were not aware that the research was taking place.

Several organisational changes took place in the ED during the data collection periods, 2009-2012. In December 2010 the Department of Health introduced new A&E clinical quality indicators for launch in April 2011 (DH, 2010a). This set of measures replaced the previous single measure of performance, the four-hour standard. Indicator 6 was concerned with the initial assessment (triage) of patients arriving by ambulance. It set a standard that 95% of patients arriving by ambulance should receive an assessment, which includes a brief history, pain and early warning scores within 15 minutes of arrival. In order to meet this new standard nursing staff were deployed differently. To ensure that all patients who arrived by ambulance received a prompt assessment a Registered Nurse was designated   to   ‘Ambulance   Triage’.   An   area   with   two   cubicles   to   accommodate   ambulance stretchers was created. Prior to this change the shift leader (a senior clinical nurse) triaged all the patients arriving by ambulance as well as being responsible for the overall management of the ED. This change coincided with the post-eTriage data collection from April 2011. Secondly, in November 2011 a co- located children’s   ED   opened.   From   this   date all children received their triage assessment in the children’s  ED  by  Registered  Children’s  Nurses.  This  change  was   in place for the final data collection point of January 2012. See Table 4.1 for a timeline of these operational changes.

Table 4.1 Timeline illustrating operational changes within the ED during the study period

eTriage Pre eTriage data collection period Launch of eTriage April 2010

Post eTriage data collection period Time periods April Jan 2009 2010 April Jan 2011 2012 Triage processes and operational changes Patients arriving by ambulance assessed by Nurse-in-Charge (senior nurse). Walk-in patients assessed by Registered Nurse (RN) triage nurse in one of two triage cubicles situated in the ED waiting room April 2011 Designated ambulance RN triage nurse Adult “walk-in”   triage now in one cubicle in ED waiting room November 2011 All children now triaged in  children’s   ED by RN (Child)

Additionally from 20th December 2012 until 27th March a project ran in the ED