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Literature Searching

Follow our step-by-step guide to help you carry out a good literature search

Develop your research question and search strategy

Sometimes it helps to write an answerable question that begins and ends with a patient, population, or problem. This helps to develop a clinical research and/or EBP question.  Using one of the frameworks below for developing searchable and answerable clinical questions can be useful  during the research process. 

Developing your research question

PICO is most widely used in quantitative research questions. Originally designed for questions that include interventions or comparisons which can make it difficult if these elements are not included in your research question.

P

Population, Patient, Problem Who are the users, patients or community affected? What are their symptoms, age, gender etc.
I Intervention What is being done for patient/population e.g. screening, surgery, rehabilitation, services etc.
C Comparison Is there a comparison? e.g different treatment options, placebos etc.
O Outcome What do you hope to achieve? What changes or measures for patient/population?

e.g.

P

Population, Patient, Problem Female patients.
I Intervention chemotherapy
C Comparison surgery
O Outcome better recovery

USING PICO TO FORM YOUR RESEARCH QUESTION

Is Chemotherapy (intervention) more efficient than Surgery (comparison) in managing stage 1 breast cancer (problem) for women patients (population)?

*Note: It is not necessary to use every element in PICO or to have both a problem and population in your question. PICO is a tool that helps researchers frame an answerable EBP question.

Example article using PICO, PICOS and SPIDER

 

Similar to PICO with type of Study added. PICOS is most widely used in quantitative research questions. Originally designed for questions that include interventions or comparisons which can make it difficult if these elements are not included in your research question.

P Patient, Population, problem Who are the users, patients or community affected? What are their symptoms, age, gender?
I Intervention What is being done for patient/population e.g. screening, surgery, rehabilitation, services
C Comparison Is there a comparison? e.g. different treatment options, placebos etc.
O Outcome What do you hope to achieve? What changes or measures for patient/population?
S Study design RCTs? Quantitative studies? This can help reduce irrelevant records

e.g.

P Patient, Population, problem Female adults with depression
I Intervention antidepressant medication
C Comparison exercise
O Outcome improved quality of life
S Study design Quantitative studies

USING PICOS TO FORM YOUR RESEARCH QUESTION

How many adult females with depression (P) have an increased quality of life (O) with regular exercise (C) compared to using antidepressant medication (I)?

Example article using PICO, PICOS and SPIDER

Similar to PICO with Time added. PICOT is most widely used in quantitative research questions. Originally designed for questions that include interventions or comparisons which can make it difficult if these elements are not included in your research question.

P Population, Patient, Problem Who are the users, patients or community affected? What are their symptoms, age, gender?
I Intervention What is being done for patient/population e.g. screening, surgery, rehabilitation, services
C Comparison Is there a comparison? e.g. different treatment options, placebos etc.
O Outcome What do you hope to achieve? What changes or measures for patient/population?
T Time Time describes the duration of your data collection

e.g.

P Population, Patient, Problem Adults with back pain
I Intervention physiotherapy
C Comparison exercise
O Outcome increase mobility
T Time Data will be collected daily for 6 weeks

USING PICOT TO FORM YOUR RESEARCH QUESTION

Does physiotherapy (I) increase mobility (O) in adults with back pain (P) compared to daily exercise (C) at 6 weeks (T)?

Example article using PICOT

 

PEO is most useful for qualitative research questions.

P Patient, Population, Problem Who are the patients or community being affected? What are their symptoms, age, gender etc?
E Exposure Is the population exposed to a condition or illness, risk factor, screening, rehabiltation, services?
O Outcomes or themes patient experiences. Are you looking for improvements in pain, responsiveness to treatment, mobility, quality of life?

e.g.

P Patient, Population, Problem Adult females using HRT
E Exposure Breast Cancer
O Outcomes or themes Daily living, quality of life

USING PEO TO FORM YOUR RESEARCH QUESTION

Does the quality of life (O) change when women on HRT (P) are diagnosed with breast cancer (E)?

 

Similar to PEO. PIO is most useful for qualitative research questions

P Patient, Population, Problem Who are the patients or community being affected? What are their symptoms, age, gender etc?
I Intervention
What is being done for patient/population e.g. screening, surgery, rehabilitation, services etc.
O Outcomes or themes patient experiences. Are you looking for improvements in pain, responsiveness to treatment, mobility, quality of life?

e.g.

P Patient, Population, Problem adult males smokers
I Intervention using nicotine patches
O Outcomes or themes smoking cessation

USING PIO TO FORM YOUR RESEARCH QUESTION

How effective is nicotine patches (I) in encouraging adult males (P) in smoking cessation (O)? 

SPICE is good for formulating questions about qualitative or improvement research. Qualitative research is generally when you want to explore perspectives or opinions about a topic.

S Setting Where?
P Perspective for Whom?
I Intervention What?
C Comparison Compared with what?
E Evaluation with what Result?

e.g.

S Setting hospital
P Perspective children under 19 years of age
I Intervention allergy testing
C Comparison community
E Evaluation improved treatment

USING SPICE TO FORM YOUR RESEARCH QUESTION

What is the impact of referrals (E) to hospital (S) of offering primary/community (C) allergy testing (I) for children under the age of 19 years old (P)?

 

SPIDER can be useful for quantitative, qualitative or mixed methodology research questions. This can be used when the research is about attitudes and experiences rather than scientifically measurable data. It involves applying the right criteria to your question by focussing less on the intervention and more on the design of the study, and deals with "samples" rather than a "patient" or "populations". Research questions framed using the SPIDER tool tend to begin with "What are the experiences of ...?"

S Sample The group of participants in qualitative research
PI Phenomona of interest The how and why of behaviours and experiences
D Design How the study was devised and conducted
E Evaluation
The measurement of outcome might be subjective and not necessarily empirical
R Research type Qualitative, or quantitative, or mixed?

e.g.

S Sample First year university students
PI Phenomona of interest Full time online learning
D Design Survey
E Evaluation Experiences
R Research type Qualitative

USING SPIDER TO FORM YOUR RESEARCH QUESTION

What are the experiences (E) of first year university students (S) using full time online learning (PI): a qualitative study (R)?

Example article using PICO, PICOS and SPIDER

 

FINER can be useful for quantitativequalitative or mixed methodology research questions. FINER allows researchers to ponder the philosophical, logical, and scientific implications of writing research questions. It involves applying the right criteria to your question.

F Feasibility Adequate number of subjects, expertise. Affordable in time and money in manageable scope.
I Interesting obtaining the answer should be interesting to science/health community
N Novel should confirm, extend or refute previous findings
E Ethical amenable to a study that institutional review board would approve
R Relevant to scientific knowledge, clinical and health policy and future research

 

TRIP database

Try using the PICO search option in TRIP for systematic reviews, meta analyses etc.

How the PICO search works in Trip Pro