These recommendations are based on evidence from observational studies on the causes of tiredness, evidence on perceptions of the causes of tiredness, and on expert opinion from narrative reviews.

Nature of fatigue

• The recommendation to ask the person to say what they mean by tiredness or fatigue, and its justification, are derived from expert opinion in narrative reviews [Morrison and Keating, 2001; Rosenthal et al, 2008].
• Other recommendations on establishing the nature of tiredness are based on a National Institute for Health and Clinical Excellence guideline on the diagnosis and management of chronic fatigue syndrome (CFS)/myalgic encephalomyelitis or encephalopathy (ME) [National Collaborating Centre for Primary Care, 2007] and expert opinion from narrative reviews [Ruffin and Cohen, 1994; Rodriguez, 2000; Morrison and Keating, 2001; Simon, 2008].

Eliciting concerns and perceptions

• The recommendation to elicit the person's concerns and perceptions of the cause of their tiredness is based on expert opinion [Ridsdale, 1989; Godwin et al, 1999; Rodriguez, 2000; Moncrieff and Fletcher, 2007], as well as the following:
• There is evidence from a UK study (n = 151) that at least half of people with chronic tiredness attribute their symptoms to a physical cause [Darbishire et al, 2003].
• There is evidence from a study of 220 people presenting to one of four general practices in the UK that GPs tend to perceive the cause of tiredness as psychological, whereas people with tiredness are more likely to perceive the cause as physical [Ridsdale et al, 1993; Ridsdale et al, 1994].
• One of the management strategies proposed in the literature is for the primary healthcare professional to try to broaden the person's perception of fatigue, so that psychosocial causes and solutions are validated and considered along with biomedical causes [Ruffin and Cohen, 1994].

Sleep history

• This recommendation is based on expert opinion from narrative reviews [Rodriguez, 2000; Morrison and Keating, 2001; Rosenthal et al, 2008].

Lifestyle and psychosocial history; screening for depression and anxiety

• These recommendations are based on expert opinion from narrative reviews [Godwin et al, 1999; Rodriguez, 2000; Ebell and Belden, 2001; Morrison and Keating, 2001; Rosenthal et al, 2008; Simon, 2008] and on limited evidence from mainly observational studies that, in people presenting to primary care with a complaint of tiredness or fatigue, the underlying cause is commonly psychological or psychosocial (in 18–62% of people), or there is an associated psychological disorder or psychosocial problem.
• The screening questions are derived from the National Institute for Health and Clinical Excellence guideline, Depression (amended): management of depression in primary and secondary care [NICE, 2007a].

Medication

• This recommendation is based on expert opinion from narrative reviews [Godwin et al, 1999; Rodriguez, 2000; Morrison and Keating, 2001; Rosenthal et al, 2008; Simon, 2008].

Other symptoms/history

• This recommended list is derived from narrative reviews [Rodriguez, 2000; Morrison and Keating, 2001] and from a North of England guideline on the medical assessment of people with suspected CFS/ME, which states that perennial rhino-sinusitis commonly causes fatigue [Spickett, 2009].

At risk of HIV, hepatitis, or tuberculosis

• This recommendation is based on expert opinion from a narrative review and a New Zealand guideline [Ruffin and Cohen, 1994; BPAC NZ, 2006].

Examination

• CKS found no evidence on the diagnostic yield of a physical examination (or its constituents) for people with tiredness presenting to primary care. However, a physical examination is good medical practice and generally regarded (in narrative reviews) as appropriate [Ruffin and Cohen, 1994; Epstein, 1995; Ebell and Belden, 2001; Morrison and Keating, 2001; Sharpe and Wilks, 2002; Cornuz et al, 2006; Rosenthal et al, 2008].
• Several authors suggest that a physical examination reassures the person (in particular, that their problem is being taken seriously) and cements the therapeutic relationship [Ruffin and Cohen, 1994; Cornuz et al, 2006; Moncrieff and Fletcher, 2007].
• In a specialist US chronic fatigue clinic, physical examinations were judged to have provided diagnostic information in only 2% of people [Lane et al, 1990]. However, a specialist clinic would exclude people for whom a diagnosis had already been made in primary care, and CKS expert reviewers report higher yields in secondary care.
• Some authors recommend a complete examination, particularly if the history does not suggest a cause [Ruffin and Cohen, 1994; Epstein, 1995; Rodriguez, 2000; Murtagh, 2003; Simon, 2008], while others recommend a more focused examination, guided by the history [Godwin et al, 1999; Moncrieff and Fletcher, 2007].
• The recommendation to delay a complete physical examination until a second, longer consultation, if necessary, is derived from narrative reviews [Ruffin and Cohen, 1994; Rodriguez, 2000].