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Expert Review The Digital Rectal Examination

Anna Shirley* and Simon Brewster#

…………………………………………………………………………………………………………………………………….. The Journal of Clinical Examination 2011 (11): 1-12

Abstract Digital rectal examination is an important skill for medical students and doctors. This article presents a comprehensive, concise and evidence-based approach to examination of the which is consistent with The Principles of Clinical Examination [1]. We describe the signs of common and important diseases of the rectum and, based on a review of the literature, the precision and accuracy of these signs is discussed. Word Count: 2893

Key Words: digital rectal examination, rectum,

Address for Correspondence: [email protected]

Author affiliations: *Foundation Year 1 Doctor, Charring Cross Hospital, London. #Clinical Director of Urology, Oxford Radcliffe Hospitals NHS Trust. ……………………………………………………………………………………………………………………………………..

Introduction examination early in a medical career. The value of The importance of performing a digital rectal learning how to perform the DRE is increasingly examination (DRE) in the appropriate setting is being recognised across UK medical schools, and captured by the phrase, “If you don’t put your finger rectal examination mannequins are now used in in it, you put your foot in it.” – H. Bailey 1973 [2]. student training and beyond. They may also be Anorectal or urogenital symptoms account for 5- used to assess the skill in Objective Structured 10% of all general practice consultations [3] and the Clinical Examinations. DRE is part of the assessment of these. In addition, statistics from 2008 show that colorectal and The Context of the DRE cancer were the third and forth most There are many circumstances in which a DRE is commonly diagnosed cancers in the UK considered to be appropriate. It has even been respectively (excluding non-melanoma skin cancer), suggested that a DRE should be considered in all [4] and 22% of colorectal cancers occur in the rectum patients aged over 40 years who are admitted to [5]. DRE is an essential component of a complete hospital, unless there is a specific contraindication (See The JCE Expert [8]. The most common presentations in which a DRE Review: Examination of the Gastrointestinal System may be appropriate as part of their assessment are [6]), a urological, and sometimes a gynaecological listed in Table 1. examination. Anatomy of the Rectum and Anus The DRE is frequently cited by medical students as Interpretation of findings on DRE requires a way of completing the abdominal examination but knowledge of the anatomy of the rectum and anus, it is often not performed in practice. However, it is and of the surrounding structures. The rectum is essential that this skill is learned, as it is an approximately 12 cm long. It begins at the important part of clinical examination for Foundation termination of the sigmoid colon and is continuous Doctors and beyond. A study of final year medical with the distally [5]. Anteriorly, the upper students at one UK medical school revealed that two-thirds of the rectum are covered with 42% had performed fewer than five DREs before . The anal canal is approximately 3-4cm qualifying, and lack of confidence in the skill was long [9], and its skin merges with the perianal skin at commonly reported [7]. The same study recorded the anal verge. There are two muscular anal that junior doctors perform DREs regularly, and this : the internal anal , which is highlights the need for proficiency in this physical involuntary; and the external anal sphincter, which 1

is under voluntary control. The function of the rectum is to permit voluntary defaecation [5]. It is important to consider the anatomy of the rectum in relation to surrounding structures, which can be assessed when performing a DRE. In a male, the base of the bladder, prostate and are situated anteriorly to the rectum, and in the female the cervix and vagina lie anteriorly.

System Symptoms/presentation Gastrointestinal Change in bowel habit, faecal incontinence Rectal symptoms: bleeding, tenesmus Unexplained iron deficiency

anaemia Figure 1 Describing the location of pathology of Unexplained weight loss the rectum [13] Reproduced with permission. Urological Lower urinary tract symptoms Literature Search Unexplained bone pain in males The following textbooks of clinical examination were Other Gynaecological symptoms reviewed: Trauma: secondary survey Clinical Examination: A Systematic Guide to Neurological: suspected Physical Diagnosis [8] spinal cord pathology The Ultimate Guide to Passing Surgical Clinical [9] Table 1 Clinical presentations for which digital Finals Macleod’s Clinical Examination [11] rectal examination should be considered. [12] Introduction to Clinical Examination [13] A face is traditionally used to describe the Clinical Examination location of any lesions found during the DRE, as viewed in the lithotomy position (see Figure 1). 12 o’ The PubMed database was searched using the clock is considered to be anterior, 3 o’ clock on the following Medical Subject Headings (MeSH) terms patient’s left, 6 o’ clock posteriorly and 9 o’ clock on alone or in combination: digital rectal examination, the patient’s right. The distance of the lesion from , rectum, sensitivity and the anus is also reported. The anal canal is lined specificity, statistics & numerical information, with highly vascular anal cushions, which help with predictive value of tests. the maintenance of continence. Their arterial supply is from the rectal arteries, and they drain via the The free text terms: rectal, rectal cancer, prostate superior rectal vein. Haemorrhoids, one of the cancer, , acute abdomen, trauma, commonest pathologies of the anorectal region, are examination, faecal incontinence were combined with the MeSH terms. abnormal anal cushions with congested vasculature and dilated venous components. They typically occur at 3, 7 and 11 o clock. They are not palpable Clinical prediction rules were searched for the on DRE unless they are thrombosed, in which case rectum. The Rational Clinical Examination Series of the Journal of the American Medical Association; a tense, tender swelling may be palpated. First degree haemorrhoids remain inside the anus, clinicalevidence.bmj.com and Evidence Based degree haemorrhoids prolapse on straining Medicine Online were searched with the terms [14,15,16]. but spontaneously return, and third degree ‘rectum’ and ‘digital rectal examination Related articles were also evaluated. Relevant haemorrhoids remain prolapsed unless manually articles available through Oxford University e- returned. Prolapsed haemorrhoids may be visible on resources were selected. inspection during the DRE [10].

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Preparation Ensure the examination environment is appropriate considered in the gynaecological setting for in terms of privacy. Wash your hands and introduce assessment of the pelvic organs [5]. yourself to the patient. Check the patient’s identity, explain what you wish to do, and obtain consent for Put on non-sterile gloves. the procedure. Advise the patient that the examination should not feel painful, but that there may be some mild discomfort. The patient may also experience the desire to defaecate, and should be warned of this. A study of 269 patients investigating the acceptability of the DRE as part of screening found that 59.4% of patients considered this to be an acceptable examination, with the figure rising significantly to 91.5% after the examination [17]. This highlights the importance of explanation and reassurance before the examination.

The DRE is considered an intimate examination, so Figure 2 Position of the patient when it is important to offer a chaperone, as advised by performing a digital rectal examination Initial the Medical Defence Union [18]. The name and role Inspection of the chaperone, or “chaperone was offered but declined”, should be documented in the notes. The examination begins with an inspection of the Gather the equipment needed, see Table 2. natal cleft (the groove between the buttocks) and the anus and perianal skin. Part the buttocks gently and inspect the skin of the natal cleft from the Equipment Needed for Digital Rectal sacrum to the perineum, and the anus (see Figure Examination 3). Refer to Table 3 for a description of lesions that Non-sterile gloves may be visible on initial inspection. In the presence Lubricant Jelly of an anal fissure, the DRE may be exquisitely Cotton wool tender, so it may be appropriate to anaesthetise the Tissue area with lidocaine gel beforehand [12].

Table 2 Equipment needed for a digital rectal examination

Position of the patient Ask the patient to undress from the waist downwards, including undergarments. He/she should be allowed to do this in private and a gown used to preserve modesty until the examination is performed. The patient should be positioned lying on the couch in the left lateral position, facing away from the examiner (see Figure 2). Ask the patient to draw his/her legs up towards the body. Figure 3 Initial inspection of the natal cleft An alternative, but less favoured approach, is to ask the patient to stand over the examining couch in a The patient should then be asked to strain, or ‘bear bent over position with his/her resting on the down’. Observe the descent of the perineum. couch. Although useful for assessing the prostate, it Excessive descent suggests a laxity of the is inadequate for assessing the rectum as a whole perineum. Look for any sign of [19]. However, this position may be more suitable for (which in the early stages is just mucosal) or the elderly or those with reduced mobility. The prolapse of haemorrhoids. Rectal prolapse lithotomy position is another alternative and may be originates from the rectum, higher than the origin of haemorrhoids, and appears as a mass with 3

concentric rings of mucosa, whereas haemorrhoids exhibit radial folds. However, it is not always easy to Lubricate the index finger of your gloved right hand tell them apart; they may coexist, and a contrast with a water-based lubricant such as K-Y Jelly. defecogram (a radiological study) may be required Kneel down bedside the examination couch. Warn to diagnose rectal prolapse. Look also for a the patient that you are about to examine the patulous anus, which appears wide open and is due rectum. Place the gloved finger on the anal margin to reduced tone in the sphincter muscles, and for and gently apply pressure to enter the anal canal any sign of faecal incontinence [19]. and rectum. To begin with, the pulp of the examining finger should be facing the 6 o clock Pathology of the Description position (see Figure 5a). Aim your finger slightly Natal Cleft and posteriorly, following the curve of the sacrum [8]. Anus Viral warts Papillomata with a rough, white surface surrounding the anus Skin tags Pedunculated, flesh- coloured perianal skin growths Anal fissures Tear in the anal wall, commonly posteriorly in the midline. Fistulae The opening may be visible as a red, pouting structure near the anus External Bluish swellings protruding Haemorrhoids from the anus Rectal Prolapse Folds of red mucosa protruding from the anus

Crohn’s disease Blue-tinged perianal skin, fistulae, fissures, skin tags Figure 4 Testing perianal sensation: Dermatitis Red, inflamed skin dermatomes S2,S3,S4. Adapted from reference [13] Anal Carcinoma Mass may be visible at the 13 . anal verge

Table 3 Pathology of the Natal Cleft and Anus. Adapted from References 8 and 13 [8,13].

Sensation and the Perineal Reflex The sensory dermatomes of the perianal region are S2, S3 and S4. To test sensation, use cotton wool to stroke lightly the areas that correspond to these dermatomes (see Figure 4) and ask the patient if he/she can feel the cotton wool in each of these areas. To test the perineal reflex (anal reflex, anal wink), use cotton wool to stroke the skin immediately around the anus, and observe for Figure 5a Palpation of the rectum in the 6 contraction of the anus (by the anal sphincter o’clock position muscles). Impaired perianal sensation and an absent or reduced perineal reflex may indicate S2-4 Assessment of Anal Tone nerve root or spinal cord pathology, for example On entering the anal canal, an initial judgment of the cauda equina syndrome, in which the sacral nerve anal tone at rest can be made. Then ask the patient roots may be compressed. A more detailed to ‘bear down’ and squeeze your finger, to assess may be then be required the anal sphincter further in terms of strength and

symmetry. Reduced or absent tone may indicate 4

spinal cord injury. DRE has traditionally been rectum can be felt as a tight, narrow region and may considered a part of the secondary survey of the indicate anal, rectal or prostate carcinoma. Advanced Trauma Life Support protocol to examine for this [20], as well as to detect a “high-riding” prostate (the prostate is difficult to feel or only its base is palpable) in males with urethral injury, and to determine if a pelvic fracture is open (to the ), or closed. Few studies have assessed how useful the DRE is for detecting spinal cord injury, but there is evidence to suggest that its findings must be considered in the context of other clinical signs, and in the absence of reduced anal tone, spinal cord injury cannot be excluded (see Evidence Box 1). Assessment of anal tone is also used in the evaluation of faecal incontinence, and Figure 5b Palpation of the rectum in the 12 findings on DRE have been shown to correlate well o’clock position with recordings from anal manometry [22,23].

Palpation of the Rectum Site of origin Mass Normally, the coccyx and sacrum can be felt of pathology posteriorly. Different authors disagree about the Rectum Faeces direction in which to palpate the circumference of Rectal carcinoma the rectum, though the most important point is that Rectal [8,9,11-13] the entire rectum must be palpated . A Foreign body popular way is described here. From the 6 o’clock Sigmoid colon Prolapsed sigmoid carcinoma position, supinate your arm to examine the right posterolateral rectal wall, until the 9 o’ clock position Pelvis Pelvic metastases is reached. Return to the 6 o clock position, and Uterine malignancy pronate your arm 90° to the 3 o’ clock position to Ovarian Malignancy examine the left posterolateral rectal wall. Continue Cervical carcinoma pronating your arm round to the 12 o’clock position, Endometriosis and beyond this to the 9 o’clock position, to Pelvic Abscess examine the anterolateral rectal walls. Return to the Prostate Prostate carcinoma 12 o’clock position (see Figure 5b). The entire Benign Prostatic Hypertrophy rectum is therefore assessed for tenderness and any palpable masses. This may detect a rectal Prostatic Abscess carcinoma, which feels hard and irregular, however Table 4 Causes of a palpable mass on digital there are many causes of a palpable rectal mass rectal examination. Adapted from Reference 8[8]. (see Table 4). There is little evidence available as to how useful the DRE is for detecting rectal The DRE is performed on nearly all patients carcinoma, but one study in the setting of general presenting with an acute abdomen, and the practice concluded that it should not be relied upon presence of tenderness has been reported to be alone (see Evidence Box [24]. one of the more useful signs identified during this examination [5]. It may indicate the presence of The rectum may be loaded with faeces, which is a inflammatory bowel disease, , ovarian common finding in patients with . These abscesses and cysts, and appendicitis. However, are typically moveable and indentable [11]. In the the evidence for the latter is variable, and suggests presence of a palpable rectal mass, it may be that the DRE is not very sensitive for detecting appropriate to repeat the examination after the appendicitis, and provides additional useful patient has defaecated, to exclude faeces as a information only if the diagnosis is in doubt following cause. Note that haemorrhoids are not palpable on taking and examination of the abdomen, in DRE unless they are thrombosed. In addition to which case other pathology should be suspected palpable masses, stenosis of the anal canal or (see Evidence Box 3) [25,26,27]

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Prostate examination Further tests The prostate is examined in males at the end of the There is also the option of testing for pelvic floor rectal examination when the examining finger is in dyssynergia, in which the external anal sphincter the 12 o’ clock position. One small study using a contracts instead of relaxes when the patient strains DRE simulator found that a higher magnitude of to defaecate. This is a common cause of chronic finger pressure led to the detection of smaller constipation. To test for this, ask the patient to strain prostate abnormalities, so it is important to ensure trying to push your finger out. Paradoxical tightening adequate pressure when palpating the prostate [28]. of the musculature suggests dyssynergia. The DRE The prostate should be assessed for consistency, has been shown to be a very useful test for nodularity, size and symmetry. The normal prostate identifying this (see Evidence Box 5) [35]. feels firm with a smooth, regular surface and is symmetrical [29]. It is approximately 3.5cm wide and Completing the Examination protrudes approximately 1cm into the rectal lumen. Always inspect the gloved finger for the nature and There are two lobes separated by a palpable colour of the stool, and note the presence of any longitudinal sulcus. It is not always possible to feel blood or mucus. Black tarry stools may represent the base of the gland but if it is small one can easily melaena, which occurs as the breakdown product of get above it. blood, indicating an upper gastrointestinal bleed. The stool may also appear dark if the patient is Enlargement of the prostate gland occurs in benign taking oral iron supplements. Pale, offensive stools prostatic hypertrophy, and its smooth, symmetrical occur in situations of malabsorption. Pale stools properties are typically maintained. Prostate size may also be found in patients with obstructive determined by digital rectal examination has been jaundice, along with dark urine. Fresh blood on the found to correlate significantly with transrectal surface of, or mixed in with stool suggests bleeding ultrasound measurements, though gives a slight from the large bowel, rectum or anus. underestimate for larger sizes [30] Prostate cancer is suggested by a hard, irregular asymmetrical There is also the option for performing a faecal prostate, with the sulcus not palpable between the occult blood test (FOBT) at this stage, as part of a lobes. A of meta-analyses have evaluated screening process for . A single the role of the DRE in detecting prostate cancer, sample of the stool obtained during DRE on the and though the DRE is considered a vital part of the gloved finger is smeared on to a faecal occult blood work up for a patient with suspected prostate test card. However, this is less commonly performed pathology, evidence suggests its findings must be now as it is considered inferior to the recommended considered in the context of investigations such as sampling practice using the guaiac smear method, the prostate specific antigen (PSA) measurement which tests 3 naturally passed stools on and ultrasound scan (see Evidence Box 4) [31,32,33]. consecutive days (see Evidence Box 6) [36]. DRE has also been found to detect prostate cancer in the presence of PSA levels that are not raised [34]. Once the DRE is complete, wipe away the lubricant However the majority of cancers currently jelly and direct the patient to redress. Remove your diagnosed are in the early stages and are not gloves and wash your hands. palpable. The prostate gland is typically not tender, and tenderness may suggest or a Conflicts of Interest None declared. prostatic abscess.

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References [16] Evidence Based Medicine Online, British [1] Jopling H. The Principles of Clinical Examination. Medical Journal, http://ebm.bmj.com/ The Journal of Clinical Examination. 2006; 1: 1-6 [17] Furlan AB, Kato R, Vicentini F, Cury J, Antunes [2] Bailey H. Demonstrations of Physical Signs in AA, Srougi M. Patients’ Reactions to Digital Rectal Clinical Surgery (1973) Fifteenth Edition. Publisher: Examination of the Prostate. Int Braz J Urol. 2008 Wright, Bristol Sep-Oct;34(5):572-5 [3] van Driel MF, van Andel MV, ten Cate [18] www.the-mdu.com Hoedemaker HO, Wolf RF, Mensink HJ. Physical Diagnosis-Digital Rectal Examination. Ned Tijdschr [19] Talley NJ. How to do and Interpret a Rectal Geneeskd. 2002 Mar 16;146(11):508-12 Examination in Gastroenterology. Am J

Gastroenterol. 2008 Apr;103(4):820-2 [4] http://info.cancerresearchuk.org/cancerstats/inciden [20] Guldner GT, Brzenski AB. The Sensitivity and ce/commoncancers Specificity of the Digital Rectal Examination for Detecting Spinal Cord Injury in Adult Patients with [5] McFarlane MJ. The Rectal Examination. In: Blunt Trauma. Am J Emerg Med. 2006 Walker HK, Hall WD, Hurst JW, editors. Clinical Jan;24(1):113-7 Methods: The History, Physical, and Laboratory Examinations. 3rd edition Boston: Butterworths; [21] Shlamovitz GZ, Mower WR, Bergman J, Crisp

1990. Chapter 97 J, DeVore HK, Hardy D, Sargent M, Shroff SD, Snyder E, Morgan MT. Poor Test [6] Gardner A. Examination of the Gastrointestinal Characteristics for the Digital Rectal Examination in System. The Journal of Clinical Examination 2006; Trauma Patients. Ann Emerg Med. 2007 1: 7-11 Jul;50(1):25-33, 33.e1

[7] Turner KJ, Brewster SF. Rectal Examination and [22] Buch E, Alós R, Solana A, Roig JV, Fernández Urethral Catheterization by Medical Students and C, Díaz F. Can Digital Examination Substitute House Officers: Taught but not Used. BJU Int. 2000 for the Evaluation of Anal Sep;86(4):422-6 Canal Pressures? Rev Esp Enferm Dig. 1998

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Physical Diagnosis. Talley NJ, O’Connor S (2009) [23]Dobben AC, Terra MP, Deutekom M, Gerhards Sixth Edition. Publishers: Churchill Livingstone MF, Bijnen AB, Felt-Bersma RJ, Janssen [9] The Ultimate Guide to Passing Surgical Clinical LW, Bossuyt PM, Stoker J. Anal Inspection and Finals. Malik MF, Maula A (2010) First Edition. Digital Rectal Examination Compared to Anorectal

Publishers: Radcliffe Publishing Physiology Tests and Endoanal Ultrasonography in

[10] Surgical Talk. Goldberg A, Stansby G (2008) Evaluating . Int J Colorectal Dis. 2007 Jul;22(7):783-90. Epub 2006 Nov 10 Second Edition. Publishers: Imperial College Press

[11]. Macleod’s Clinical Examination. Douglas G, [24] Ang CW, Dawson R, Hall C, Farmer M. The Nicol F, Robertson C (2009) Twelfth Edition. Diagnostic Value of Digital Rectal Examination in Primary Care for Palpable Rectal Tumour. Publishers: Churchill Livingstone Colorectal Dis. 2008 Oct;10(8):789-92 [12] Introduction to Clinical Examination. Ford M, Japp A, Hennessey I (2005) Eighth Edition. [25] Dickson AP, MacKinlay GA. Rectal Examination and Acute Appendicitis. Arch Dis Child. 1985 Publishers: Churchill Livingstone Jul;60(7):666-7 [13] Clinical Examination. Epstein O, Perkin GD, [26] Dixon JM, Elton RA, Rainey JB, Macleod DA. Cookson J, Watt IS, Rakhit R, Robins AW, Hornett Rectal Examination in Patients with Pain in the GAW (2008) Fourth Edition. Publishers: Mosby. Right Lower Quadrant of the Abdomen. BMJ. 1991

Article Title: Examining the anus, rectum and Feb 16;302(6773):386-8 prostate p223-224. Copyright Elsevier 2008 [14] The Journal of the American Medical [27] Sedlak M, Wagner OJ, Wild B, Papagrigoriades Association Rational Clinical Examination Series S, Zimmermann H, Exadaktylos AK. Is There Still a http://jama.ama- Role for Rectal Examination in Suspected Appendicitis in Adults? Am J Emerg Med. 2008 assn.org/cgi/collection/rational_clinical_exam Mar;26(3):359-60

[15] clinicalevidence.bmj.com 7

[28] Wang N, Gerling GJ, Krupski TL, Childress [33] Song JM, Kim CB, Chung HC, Kane RL. RM, Martin ML. Using a Prostate Exam Simulator to Prostate-Specific Antigen, Digital Rectal Decipher Palpation Techniques that Facilitate the Examination and Transrectal Ultrasonography: A Detection of Abnormalities Near Clinical Limits. Meta-Analysis for this Diagnostic Triad of Prostate

Simul Healthc. 2010 Jun;5(3):152-60 Cancer in Symptomatic Korean Men. Yonsei Med

J. 2005 Jun 30;46(3):414-24 [29] Deshpande AR, Block N, Barkin JS. Taking a Closer Look at the Rectal Examination: Beyond the [34] Okotie OT, Roehl KA, Han M, Loeb S, Gashti

Basics. Am J Gastroenterol. 2009 Jan;104(1):246-7 SN, Catalona WJ. Characteristics of Prostate

[30] Roehrborn CG, Girman CJ, Rhodes T, Hanson Cancer Detected by Digital Rectal Examination Only. Urology. 2007 Dec;70(6):1117-20 KA, Collins GN, Sech SM, Jacobsen SJ, Garraway WM, Lieber MM. Correlation Between Prostate Size [35] Tantiphlachiva K, Rao P, Attaluri A, Rao SS. Estimated by Digital Rectal Examination and Digital Rectal Examination is a Useful Tool for Measured by Transrectal Ultrasound. Urology. 1997 Identifying Patients with Dyssynergia. Clin

Apr;49(4):548-57 Gastroenterol Hepatol. 2010 Nov;8(11):955-60.

Epub 2010 Jul 23 [31] Hoogendam A, Buntinx F, de Vet HC. The Diagnostic Value of Digital Rectal Examination in [36] Collins JF, Lieberman DA, Durbin TE, Weiss Primary Care Screening for Prostate Cancer: a DG. Accuracy of Screening for meta-analysis. Fam Pract. 1999 Dec;16(6):621-6 on a Single Stool Sample Obtained by a Digital [32] Mistry K, Cable G. Meta-Analysis of Prostate- Rectal Examination: a Comparison with Specific Antigen and Digital Rectal Examination as Recommended Sampling Practice. Ann Intern Med. Screening Tests for Prostate Carcinoma. J Am 2005 Jan 18:142(2):81-5

Board Fam Pract. 2003 Mar-Apr;16(2):95-101

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Question. Does this patient have spinal cord injury based on findings from the DRE? Reference. Guldner and Brzenski (2006) [20]. Population. 1032 patients over 15 years of with blunt trauma. Incidence. 5.2% Details of Study. Retrospective review. Comparator. Diagnosis of Spinal Cord Injury on discharge, according to the International Classification of Diseases, Ninth Revision (ICD-9). Sensitivity. See Table Specificity. See Table. Conclusion. The DRE is insensitive to spinal cord injury, but highly specific. A negative DRE cannot rule out spinal cord injury. Reduced or absent rectal tone on DRE should be interpreted in the context of the pre-test probability of spinal cord injury.

Question. Does this patient have spinal cord injury based on findings from the DRE? Reference. Shlamovitz et al (2007) [21]. Population. 1401 Incidence. 3% Details of Study. Retrospective review. Comparator. Spinal cord injury on imaging or operation reports, or new parapleagia/quagriplegia/spinal injury diagnosis. Sensitivity. See Table Specificity. See Table. Conclusion. Due to its poor sensitivity for detecting spinal cord injury, the DRE should not be used as a screening tool in trauma cases. The DRE cannot rule out spinal cord injury.

Author N Sensitivity (%) Specificity (%) Guldner GT 2006 [20] 1032 50 93 Schlamovitz GZ 2007[21] 1401 37 96

Evidence Box 1 The digital rectal examination in spinal cord injury.

Question. Does this patient have a rectal tumour on DRE by the general practitioner? Reference. Ang et al (2008) [24]. Population. 1069 patients referred to the colorectal cancer referral service by GPs. Incidence. 3.93% Details of Study. Retrospective review of hospital data. Comparator. DRE performed in the specialist clinic. Sensitivity. 76.2% Specificity. 91.7% Conclusion. In the primary care setting, although the specificity and sensitivity of DRE for detecting rectal tumours are high, there was a high false positive rate, so DRE should not be used alone in the diagnosis of a rectal tumour, but in the context of other findings.

Evidence Box 2 Identifying a rectal tumour on digital rectal examination.

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Question. Does this patient have appendicitis based on DRE? Reference. Dickson et al (1985) [25]. Population. 328 patients aged 14 and under with suspected appendicitis. Incidence. 31.4% Details of Study. Prospective study. Comparator. Histology of resected appendix Sensitivity. See table. Specificity. See table. Conclusion. More than 90% were correctly diagnosed with appendicitis based on history and abdominal signs alone, without information from DRE. DRE may therefore be more useful if the diagnosis remains uncertain after this initial assessment and other pelvic pathology is suspected.

Question. Does this patient have appendicitis based on DRE? Reference. Dixon et al (1991) [26]. Population. 1028 patients with right lower quadrant pain who underwent DRE. Incidence. 37.3 Details of Study. Prospective study. Comparator. Histology of resected appendix. Sensitivity. See table. Specificity. See table. Conclusion. Although tenderness on DRE was more common in patients with appendicitis than other diagnosed conditions, if rebound tenderness was , the DRE provided no further useful information.

Question. Does this patient have appendicitis based on DRE? Reference. Sedlak et al (2007) [27]. Population. 577 patients aged over 16 with right lower quadrant pain who underwent DRE Incidence. 40.4% Details of Study. Retrospective review of medical records. Comparator. Histology of resected appendix Sensitivity. See table. Specificity. See table. Conclusion. The DRE is not helpful in making the diagnosis of appendicitis or in guiding the decision whether to proceed to surgery.

Author N Sensitivity(%) Specificity(%) Dickson 1985 [25] 328 9 88 Dixon 1991 [26] 1401 34 72 Sedlak 2007 [27] 577 36.5 61.5

Evidence Box 3 Identifying appendicitis on digital rectal examination.

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Question. Does this patient have prostate cancer on DRE? Reference. Hoogendam et al (1999) [30]. Population. ~22,000 men from unselected populations. Incidence. 1.2 – 7.3% Details of Study. Meta- analysis of 14 studies, 5 considered ‘good quality’. Comparator. or surgery. Sensitivity. See Table. Specificity. See Table. Conclusion. DRE is highly specific for the detection of prostate cancer but the sensitivity is low. It should not be used alone to diagnose or exclude prostate cancer.

Question. Does this patient have prostate cancer on DRE? Reference. Mistry and Cable (2003) [31]. Population. 47,791 men. Most studies included asymptomatic men aged over 50 years. Incidence 1.8% Details of Study. Meta-analysis of 13 studies. Comparator. Prostate biopsy. Sensitivity. See Table. Specificity. See Table. Conclusion. Prostate specific antigen measurement had a higher sensitivity and specificity for detecting cancer than did DRE. PSA and DRE together detected 83.4% of early, localised prostate cancer.

Question. Does this patient have prostate cancer on DRE? Reference. Song et al (2005) [32]. Population. 2029 men with lower urinary tract symptoms or benign prostatic hyperplasia. Incidence. 25.4% (13.5-41.5%). Details of Study. Meta-analysis of 13 studies. Comparator. Prostate biopsy. Sensitivity. See Table. Specificity. See Table. Conclusion. The findings on DRE are best considered as part of a triad along with Prostate Specific Antigen measurement and Transrectal Ultrasound scanning.

Author Studies Sensitivity(%) Specificity(%) Hoogendam A 1999[30] 14 59 94 Hoogendam A 1999[30] 5 good quality 64 97 Mistry K 2003[31] 13 53.2 83.6 Song JM 2005[32] 13 68.4 71.5

Evidence Box 4 Identifying prostate cancer on digital rectal examination.

Question. Does this patient have dyssynergia? Reference. Tantiphlachiva et al (2010) [35]. Population. 209 consecutive patients with Rome III criteria for chronic constipation Incidence. 87% Details of Study. Prospective study. Comparator. Physiological test results Sensitivity. 75% Specificity. 87% Conclusion. The DRE is a useful tool in identifying patients with dyssynergia, and could help select patients for further investigation and treatment.

Evidence Box 5 Identifying dyssynergia on digital rectal examination.

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Question. Is a stool sample obtained by DRE as accurate as naturally passed stool for faecal occult blood test (FOBT) sampling when screening for colorectal cancer? Reference. Collins et al (2005) [36]. Population. 2665 asymptomatic patients aged 50-75. Incidence. 10.7% Details of Study. Prospective cohort study. Comparator. . Sensitivity. See table. Specificity. See table. Conclusion. Digital FOBT is a poor screening tool for colorectal cancer, and a negative result cannot exclude advanced disease. Alternative tests such as the at-home 6 sample FOBT are preferred, and the digital FOBT should not be used alone. Method of FOBT Sensitivity (%) Specificity (%) Digital FOBT 4.9 97.5 At-home 6 sample FOBT 23.9 93.9

Evidence Box 6 Comparing methods of obtaining stool sample for faecal occult blood testing

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