Using Picot Format in an Integrative Review of Literature

• Journal List
• BMJ Open
• 5.6(11); 2016
• PMC5129008

BMJ Open. 2016; half dozen(11): e013175.

Framing of inquiry question using the PICOT format in randomised controlled trials of venous ulcer illness: a protocol for a systematic survey of the literature

Luciana P F Abbade

¹Department of Dermatology and Radiotherapy, Botucatu Medical School, Universidade Estadual Paulista, UNESP, São Paulo, Brazil

^twoDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada

³Biostatistics Unit of measurement, Father Sean O'Sullivan Research Middle, St Joseph's Healthcare, Hamilton, Ontario, Canada

Mei Wang

²Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada

Kamath Sriganesh

⁴Department of Neuroanaesthesia, National Constitute of Mental Health and Neurosciences, Bangalore, Karnataka, India

⁵Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada

Lawrence Mbuagbaw

^twoDepartment of Clinical Epidemiology and Biostatistics, McMaster Academy, Hamilton, Ontario, Canada

³Biostatistics Unit, Begetter Sean O'Sullivan Research Centre, St Joseph's Healthcare, Hamilton, Ontario, Canada

Lehana Thabane

²Department of Clinical Epidemiology and Biostatistics, McMaster Academy, Hamilton, Ontario, Canada

³Biostatistics Unit, Father Sean O'Sullivan Enquiry Centre, St Joseph's Healthcare, Hamilton, Ontario, Canada

Received 2016 Jun 24; Revised 2016 Sep xiv; Accepted 2016 Oct eighteen.

Abstract

Introduction

Although venous ulcers have a bang-up social and economic affect, there is a lack of evidence from randomised controlled trials (RCTs) to support appropriate management for this affliction. Framing the research question using the Population; Intervention; Comparator; Outcome; Time frame (PICOT) format in RCTs tin meliorate the quality of the research design.

Objectives

To evaluate how the PICOT format is used to frame a research question in reports of RCTs of venous ulcer disease and to determine the factors associated with better adherence to the PICOT format in framing the research question.

Methods and analyses

We will conduct a systematic survey of RCTs on venous ulcers published in the National Institute of Wellness, PubMed database between Jan 2009 and May 2016. We will include all RCTs addressing therapeutic intervention for venous ulcer affliction involving human subjects, and published in the English language language. The pick process volition be carried out in duplicate past two independent investigators. Showtime, titles and abstracts will be screened, so full-text articles. We volition examine whether the 5 elements of the PICOT format are used in formulating the research question and give a score between 0 and 5. The primary upshot will exist the proportion of studies that take adequately reported all five PICOT elements.

Dissemination

This will be the first survey to assess how the PICOT format is used to frame research questions on the management of venous ulcers in reports of RCTs. On completion, this review will be submitted to a peer-reviewed biomedical journal for publication and the findings will also exist presented at scientific conferences.

Keywords: STATISTICS & RESEARCH METHODS, WOUND MANAGEMENT, Venous ulcers, Randomized controlled trial

Strengths and limitations of this report

• This will be the first review to assess how the Population; Intervention; Comparator; Outcome; Fourth dimension frame (PICOT) format is used to frame research questions in reports of randomised controlled trials (RCTs) on venous ulcers

• Selected manufactures volition be reviewed independently and in duplicate to evaluate the possible factors associated with amend adherence to the PICOT format

• Limitations: Only RCTs published in English language will be considered. Only published information volition exist used. Our findings will only be generalisable to the field of venous ulcer illness.

Introduction

Amid the chronic skin ulcers, venous ulcers (VU) are the most common. It is the advanced stage of chronic venous affliction and is more common in Western countries.¹ The prevalence of VU varies from 0.06% to 2%, occurring in ∼4% of people over 65 years.ⁱⁱ The prevalence of VUs varies essentially between studies due to differences in diagnostic methods, epidemiological characteristics of the patients and whether or not human foot ulcers are included.^{three 4} The main risk factors for VU include old age, phlebitis and deep venous thrombosis.^{1 5}

Complications arising from VU are various, primarily related to its chronicity. The main complications are critical colonisation and contact dermatitis.^{six 7} More than severe complications include cellulitis, osteomyelitis and malignant change.^{viii nine} High rates of relapse after healing is other problem with annual recurrence rates varying between 26% and 69%.^10–12 In add-on, VU comes with physical, social, economic and emotional brunt.^{xiii fourteen} The overall cost of VU handling in most Western countries is ∼1% of their entire healthcare budgets.¹⁵

Although VU has a great social and economic touch on, in that location is a lack of testify from randomised controlled trials (RCTs) to support the management of patients with VU. A recent systematic review of the trials on comparative effectiveness of avant-garde wound dressings, antibiotics and surgical management of chronic VU concluded that many of the trials had serious methodological flaws; they were small trials with limited statistical power, which in plough express their ability to provide conclusive results.¹⁶ Furthermore, a critical assessment of the bear witness in this review revealed that more trials are needed to evaluate the effects of advanced wound dressings, systemic antibiotics and surgical interventions, compared with one another or to a mandatory compression organisation established as the standard of intendance for treatment or management of patients with VU.¹⁷

Well-designed, properly conducted and appropriately reported RCTs summarised in a systematic review are considered the gold standard for providing the best evidence on the benefits and harms of different treatments for a particular affliction.^eighteen The first stride in designing an RCT is the research question (RQ). The success of whatsoever enquiry process relies, in part, on how well the investigators are able to turn a clinical problem into an RQ. This is not a simple task.¹⁹ The RQ determines the inquiry architecture, strategy and methodology.²⁰ A articulate and focused RQ will help to determine the advisable study design and the almost appropriate methods of statistical assay and sample size.^xix A well formulated research question helps to minimise error, measure out input and output variables appropriately, consider external and internal validities, limit bias and also address clinical as well every bit statistical relevance.²¹

Posing a well formulated RQ volition help the practitioner focus on the problem that is almost of import.²² The PICO format strategy for framing RQs, which was outset introduced in 1995²³ and later expanded to the acronym PICOT in 2006,²⁴ contains the post-obit 5 elements: Population or sample participants that the researcher wishes to recruit into the study, Intervention of interest, Comparator intervention or a control group to compare with the intervention of interest, Outcomes or results that will measure the effectiveness of intervention and the Fourth dimension frame over which the outcomes, are assessed.^{xix 25}

In other fields of medicine, the use of the PICOT framework is suboptimal and often associated with poor reporting of fundamental methodological issues.^{26 27}

Hypotheses

We hypothesise the following: (1) <25% of the RCTs on VU apply all the five PICOT elements in their RQ,²⁶ (2) the RQ is more likely to follow the PICOT format if the RCT is published in a periodical that endorses the Consort statement,^28–32 or has a high bear upon factor,^{30 33} is a multicentre study,³⁴ has a large sample size (>100 participants),^35–37 reports a statistically significant event for the primary outcome³⁸ and whether the trial is manufacture funded.^{35 39} These six factors were chosen based on evidence from previous research that bear witness them to be related to meliorate overall reporting quality.⁴⁰ Furthermore, the framing of the RQ using the PICOT format has likewise been shown to be independently associated with amend reporting quality.²⁶

Objectives

The purpose of this review is to generate knowledge on how researchers are framing RQs in trials on the management of VU and to provide recommendations for improvement. The specific objectives of this written report are: (ane) to assess how the PICOT format is used to frame RQs in reports of RCTs published on VU and (ii) to decide the factors associated with better adherence to the PICOT format in the framing of the RQ.

Methods

Study design

This report will be a systematic survey of the RCTs on VU published in the National Institute of Wellness, PubMed database between January 2009 and May 2016. This time frame and library were chosen primarily based on feasibility considerations. This time frame is besides part of the period during which in that location have been several published articles addressing the abyss of reporting or adherence to diverse reporting guidelines.^{40 41}

Inclusion criteria: RCTs of a therapeutic intervention for VU, involving human participants and written in English.

Exclusion criteria: Non-randomised studies, study protocols of RCTs and abstracts.

A study will be divers every bit an RCT if the consignment of participants to interventions was described past phrases such every bit 'randomly allocated', 'assigned at random' or 'allocated by randomisation', and if a control group is nowadays. The control grouping could be placebo, another treatment, a different dose of the same treatment, usual care or simply no treatment.³⁵

The search strategy will include terms for RCTs (Randomized Controlled Trial(ptyp)), venous ulcers (venous ulcers, stasis ulcers, varicose ulcers, venous stasis ulcers, venous hypertension ulcers) and exclusions for other types of articles (report protocol, review, systematic review, meta-analysis, cohort, instance–control, example series, guideline and editorial) and limits set for the specific time periods of interest (1 January 2009 to 31 May 2016). The strategy that we will adopt for the search is described in online supplementary appendix 1. The selection procedure will be carried out by 2 independent investigators (LPFA and MW) in two screening phases: title and abstract screening and full-text review. The investigators will resolve any discrepancies through consensus. First, the studies will be evaluated by reading the abstracts and simply those which fulfil the inclusion and exclusion criteria will be selected for farther screening.

Figure ane is a flow diagram showing the study selection procedures.

Flow diagram showing the study selection procedure. RCTs, randomised controlled trials; VU, venous ulcers.

Rating the framing of the RQ

We volition use the same methodology applied in a previous study.²⁶ 1 paragraph from the introduction or methods section in the total text that best describes the primary RQ, hypothesis or objective will be chosen. In that paragraph, we volition evaluate the framing of the RQ, regardless of whether it was formulated equally an RQ, hypothesis or objective. We will examine whether the v elements of the PICOT format are used. The five elements are the type of patients or population relevant to the question (P), the intervention (I), the comparative intervention (C), the outcome of involvement (O) and the time horizon for measuring the outcome (T). Nosotros will score each element every bit 1 if it was present and as 0 if it was absent. Thus, we will create a PICOT score ranging from 0 to five. The score will represent a mensurate of abyss of the clarification of the primary RQ.

Data brainchild

We will utilise a Microsoft Excel standardised data abstraction form to excerpt data from each article. To explore the possible factors that influence the framing of the RQ, boosted details will also be obtained: endorsement of the CONSORT argument, journal impact factor, whether the study was conducted at a single center or multicentre, full number of patients recruited in the study, whether the study is manufacture sponsored, and whether the study reported a statistically meaning result for the primary outcome.

Ii reviewers (LPFA and MW) will independently abstract the data and any disagreement will be resolved through consensus. If consensus cannot exist reached, a 3rd author (LT) volition be contacted.

Statistical analysis

The primary issue will be the percentage of studies that have adequately reported all five PICOT elements and the secondary outcomes will be the percentage of reporting each PICOT particular.

We volition calculate the percent of trials that conspicuously stated each PICOT element and associated 95% CI. We volition report descriptive statistics on chiselled data as numbers (percentages) and PICOT score every bit the median (IQR).

The PICOT score will be computed equally the sum of the five individual elements and volition range from 0 to 5, as described previously.²⁶ For the elements that have a 'cipher' count or 'full' counts, for example, when none of or all of the included trials reported that PICOT element, the 95% CI will be calculated past adopting the rule of three.⁴² The rule of 3 states that: if none of the n individuals reports the particular of involvement, we can exist 95% confident that the chance of this event occurring is at well-nigh three in n. For the other PICOT elements, the 95% CI of the count will be calculated by bold a binomial distribution. The probability that an RCT had clearly stated the chemical element will gear up to be the observed probability in the sample. We volition use Cohen's κ statistic to calculate chance-adjusted inter-rater agreements. Agreement volition exist interpreted as poor if κ≤0.2, fair if 0.21≤κ≤0.4, moderate if 0.41≤κ≤0.vi, substantial if 0.61≤κ≤0.viii and practiced if κ>0.8.⁴³

Nosotros will apply generalised estimating equations⁴⁴ to determine the factors associated with acceptable question formulation. The dependent variable volition be the PICOT score, ranging from 0 to 5. Adjustments volition exist fabricated for (1) whether or not the periodical endorses the Consort argument, (2) journal impact factor, (3) number of centres (multicentre versus single centre), (4) sample size (≤100 vs >100), (5) results of trial (if the primary outcome was statistically pregnant) and (six) funding status (manufacture funded versus other sources of funding).

Data volition be analysed using Statistical Package for Social Sciences (SPSS) V.16.0 (SPSS, 2009, Chicago, Illinois, USA).

Sample size calculation

The sample size was adamant based on the primary objective: estimating the proportion of studies that adequately written report all five PICOT elements using a 95% CI. On the basis of a prior estimate of the proportion of RCTs reporting 5 PICOT elements of 0.20 from a similar study,²⁶ we would require at to the lowest degree 61 RCTs to obtain an approximate of the 95% CI with a margin of error of 0.x. Table one provides a summary of the sample size estimates for different values of the margin of fault and prior estimates of the proportion of RCTs with an RQ that adequately included five PICOT elements.

Table ane

Sample size (Due north) estimates

	p
Due east	0.15	0.20	0.xxx
0.05	196	246	323
0.10	49	61	81
0.15	22	27	36

The summary of objectives, outcomes, hypotheses and methods of analysis is depicted in tabular array 2.

Table 2

Summary of objectives, outcomes, hypotheses and methods analysis

Objectives	Outcomes	Explanatory variables	Hypotheses	Methods of analyses
Primary: To appraise how the PICOT format is used to frame RQ, objectives or hypotheses based on reports of RCTs published on VU	Primary: Proportion of studies that have adequately reported all 5 PICOT elements		i. In that location are <25% RCTs most VU that adequately written report all 5 PICOT elements in the RQ	Per centum of trials that conspicuously state each PICOT element and associated 95% CI
Secondary: To determine the factors associated with better adherence to the PICOT format in framing the RQ		CONSORT endorsement past the journal Journal affect gene Number of centres (multiple centres vs a single middle) Sample size (≤100 vs >100) Results of trial (if the chief outcome was statistically significant) Funding status (industry funded vs other)	2. The utilise of the PICOT format will exist better if the journals in which it is published endorses the CONSORT statement, has a high bear upon factor, is a multicentre study, has a sample size >100, reports statistically meaning results for the primary event and is industry funded	Multivariable regression* (GEE)

Discussion and dissemination

RCTs on VUs are the all-time source of high quality evidence to provide information on the relative claim of various treatments. However, these answers are threatened by the lack of well-designed and reported clinical trials.¹⁷ Asking a skillful RQ is the first step in conducting a skilful report and improves the overall quality of the written report.²⁰ The question should be sufficiently clear, concise and directed to the heart of inquiry to be developed. The success of a scientific study depends in function on the researcher'southward power to transform the clinical problem in the fundamental RQ.¹⁹

The results of this analysis volition help to elucidate the extent to which the PICOT format is used to frame RQ in RCTs published on VU. In the event that utilize of the PICOT framework is suboptimal, this analysis will reinforce the importance of framing a expert RQ.

Ideals committee approving was not sought for this review since nosotros are dealing with published data. On completion, this review volition be submitted to a peer-reviewed biomedical journal for publication and the findings will also be presented at scientific conferences.

Footnotes

Contributors: LPFA was involved in the search strategy, design, testing of the data extraction form and writing of the initial draft. LT was responsible for the conception, design of the review and disquisitional review of the last draft. KS and MW were involved in the design and testing of the data extraction form. LM contributed to improvements in the manuscript and critically revised the final typhoon. All authors contributed to the protocol and canonical the final manuscript.

Competing interests: None declared.

Provenance and peer review: Not commissioned; externally peer reviewed.

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