Strength of evidence

This page highlights all of the Knowledge Summaries published in Veterinary Evidence by the strength of evidence found.

If no primary research literature is found following a search of the literature then that is an important finding. Particularly if the search is on an important and common question that can have a high impact on patient care. The value of finding a lack of evidence (little or no published literature) is often underestimated and overlooked; it is a key finding to drive further research and informs the current knowledge or lack thereof.

We are of the stance that a Knowledge Summary with no evidence or not enough evidence is still a valuable outcome that should be shared.

The aim of this list is to highlight the information needs and evidence gaps, currently found within veterinary literature, to both funders and researchers applying for funding.

Knowledge Summaries evaluate the strength of evidence provided by the identified papers. The clinical bottom line in a Knowledge Summary provides the reader with a qualified answer to the clinical question posed.

The strength of evidence (or the confidence in the outcomes) provided by a study can be deduced from the study type, as well as factors that increase (e.g. large sample size) or reduce (e.g. lack of blinding) the strength of evidence.

All Knowledge Summaries published within Veterinary Evidence have been categorised into the below four levels of collective evidence as outlined by the author within the clinical bottom line:

Strong evidence

Species	Title	Year	Level of evidence
Canine	In Bitches Diagnosed with Pyometra, is Medical Therapy Using Antibiosis Alone as Effective as Combining Ovariohysterectomy with Antibiosis in Reducing Morbidity and Mortality?	2016	Strong
Canine	Which is More Effective in Altering the Intra-Gastric pH in Dogs, Omeprazole or Ranitidine?	2016	Strong
Canine	Is the Use of Hypertonic Saline Effective in Reducing Intracranial Pressure After Traumatic Brain Injury in Dogs?	2017	Strong
Canine	In Dogs With Traumatic Elbow Luxation, Does Treatment Using Closed Reduction and Conservative Management Have a Better Prognosis Than Those Treated With Open Reduction and Surgery?	2017	Strong
Canine	Choosing Treatment for Dogs With Generalised Demodicosis – Isoxazolines or Imidacloprid and Moxidectin?	2019	Strong
Canine	The Use of Ultrasonography for Detection of Meniscal Damage in Dogs	2019	Strong
Canine	In dogs undergoing elective procedures is medetomidine superior to acepromazine when used as a premedication?	2020	Strong
Canine	In dogs with osteoarthritis, how effective is treatment with tramadol in providing analgesia?	2021	Strong
Equine	In an Adult Horse With Severe Asthma (Previously Recurrent Airway Obstruction) Does Using Inhaled Corticosteroids Result in an Equal Improvement in Clinical Signs When Compared to Systemic Corticosteroids?	2018	Strong
Production	Does Heat Stress Affect Immune Function in Dairy Cows?	2016	Strong
Production	Are Sand or Composted Bedding Cubicles Suitable Alternatives to Rubber Matting for Housing Dairy Cows?	2018	Strong
Production	Performance and Behavioural Effects of Separating Dairy Cows and Their Calves at Birth	2019	Strong
Production	Can vaccinating sheep reduce the occurrence of caseous lymphadenitis?	2020	Strong
Production	Age at first calving in dairy cows: which months do you aim for to maximise productivity?	2020	Strong
Small Animal	In Cats and Dogs Does Laparoscopic Ovariectomy Offer Advantages Over Open Ovariectomy for Postoperative Recovery?	2017	Strong
Small Animal	Is There Any Evidence to Support the Use of Garlic as a Wormer for Dogs and Cats in the UK?	2019	Strong
Small Animal	Comparison of 0.2 Mg/kg Vs. 1.0 Mg/kg of Oral Meloxicam for Safe and Effective Analgesia in Domestic Rabbits	2019	Strong

Moderate evidence

Species	Title	Year	Level of evidence
Canine	In Dogs With Chronic Enteropathies, Can Oral B12 Tablets Be Used to Treat Hypocobalaminaemia?	2019	Moderate
Canine	Does Pet Remedy reduce stress in dogs?	2019	Moderate
Canine	In canine acute diarrhoea with no identifiable cause, does daily oral probiotic improve the clinical outcomes?	2019	Moderate
Canine	In dogs does low level laser therapy reduce healing time?	2020	Moderate
Canine	Comparison of the safety of alfaxalone and propofol as anaesthetic induction agents in bitches undergoing c-section	2020	Moderate
Canine	In dogs with congestive heart failure, is torasemide superior to furosemide as a first line diuretic treatment?	2020	Moderate
Canine	In dogs undergoing anaesthesia do pre-anaesthetic gastroprotectants reduce gastro-oesophageal reflux?	2020	Moderate
Canine	The effect of pre-emptive incisional bupivacaine block on postoperative pain after coeliotomy in dogs	2021	Moderate
Canine	Diagnostic accuracy of cytology for canine osteosarcoma compared to histopathology	2021	Moderate
Canine	Does medical or surgical treatment for aortic stenosis improve outcome in dogs?	2021	Moderate
Canine	Trilostane monitoring in canine hyperadrenocorticism: can basal cortisol measurement replace the ACTH stimulation test?	2021	Moderate
Canine	Evaluating the reliability of computed tomography for the diagnosis of intervertebral disc extrusion in dogs	2021	Moderate
Canine	Among homeless individuals, does owning a pet improve their mental health?	2021	Moderate
Equine	Can changes in hoof wall temperature and digital pulse pressure be used to predict laminitis onset?	2019	Moderate
Equine	Continuous digital hypothermia in the prevention and treatment of acute equine laminitis	2020	Moderate
Equine	In horses undergoing volatile anaesthesia, does intraoperative alpha-2-agonist infusion improve recovery?	2021	Moderate
Equine	Can sedation be used for equine lameness investigation?	2021	Moderate
Feline	Which Antibacterial Agent Performs Best for the Treatment and Clearance of Chlamydophila Felis Infection in Cats?	2017	Moderate
Feline	In Cats Infected With Feline Herpesvirus Type-1 (FHV-1) Does Treatment With Famciclovir Result in a Reduction of Respiratory and Ocular Clinical Signs?	2017	Moderate
Feline	Cats that get stressed when visiting the veterinary practice: can gabapentin help improve their welfare?	2019	Moderate
Feline	An evaluation of the use of ronidazole for the treatment of Tritrichomonas foetus in cats	2019	Moderate
Feline	Thrombolytic Therapy in the Acute Period of Aortic Thromboembolism in Cats	2019	Moderate
Feline	Should we offer total hip replacement to feline patients?	2020	Moderate
Feline	Efficacy of EMLA™ cream for reducing pain associated with venepuncture in felines	2021	Moderate
Feline	Do papillomaviruses cause feline cutaneous squamous cell carcinoma?	2021	Moderate
Production	In newborn piglets does drying versus no intervention reduce the risk of mortality pre-weaning?	2019	Moderate
Production	Does UK licensed NSAID administration reduce signs of postoperative pain in calves castrated without local anaesthesia?	2021	Moderate
Production	Tail docking and castrating lambs: does the administration of local anaesthetic or meloxicam reduce the pain response exhibited?	2021	Moderate

Weak evidence

Species	Title	Year	Level of evidence
Canine	Is Robenacoxib Superior to Meloxicam in Improving Patient Comfort in Dogs Diagnosed With a Degenerative Joint Process?	2016	Weak
Canine	The Evidence Behind the Diagnostic Investigation of Canine Idiopathic Epilepsy	2016	Weak
Canine	The Evidence Behind the Diagnostic Investigation of Canine Idiopathic Epilepsy	2016	Weak
Canine	Is there enough evidence to recommend surgical treatment as opposed to conservative treatment for dogs affected by bicipital tenosynovitis?	2016	Weak
Canine	Are Old Dogs Who Undergo Total Hip Replacement More Predisposed to Perioperative Femoral Fractures than Young Dogs?	2016	Weak
Canine	Does Physical Therapy after a TPLO Lead to Improvement of the 1-Year Post-Operative Peak Vertical Force?	2016	Weak
Canine	Are Dogs That Eat Quickly More Likely to Develop a Gastric Dilatation (+/- Volvulus) Than Dogs That Eat Slowly?	2016	Weak
Canine	Are Dogs That Are Fed from a Raised Bowl at an Increased Risk of Gastric Dilation Volvulus Compared with Floor-Fed Dogs?	2017	Weak
Canine	Are Novel Allergen or Hydrolysed Diets an Effective Means of Reducing the Gastro-intestinal Signs in Dogs With Inflammatory Bowel Disease When Compared to Oral Prednisolone?	2017	Weak
Canine	Are Dogs Fed a Kibble-Based Diet More Likely to Experience an Episode of Gastric Dilatation Volvulus Than Dogs Fed an Alternative Diet?	2017	Weak
Canine	In Dogs With Pyothorax Does Medical Management Alone, Invasive Medical Management, or Surgical Management Result in Better Long-term Outcome?	2017	Weak
Canine	Is Alpha-casozepine Efficacious at Reducing Anxiety in Dogs?	2017	Weak
Canine	In Dogs With a European Adder Bite, Does the Use of Antivenom With Supportive Treatment Compared to Supportive Treatment Alone Improve Time to Recovery?	2017	Weak
Canine	Does Adding Transdermal Nitroglycerine to Other Therapies Used for Management of Left-sided Congestive Heart Failure in Dogs Speed the Resolution of Clinical Signs?	2017	Weak
Canine	In Dogs That Have Had Intussusception Does Enterοplication Prevent Recurrence?	2018	Weak
Canine	Do Palliative Steroids Prolong Survival in Dogs With Multicentric Lymphoma?	2018	Weak
Canine	Are Pressure Vests Beneficial at Reducing Stress in Anxious and Fearful Dogs?	2018	Weak
Canine	In Adult Dogs, Does Feeding a Raw Food Diet Increase the Risk of Urinary Calculi Formation Compared to Feeding a Complete Dry Kibble Diet?	2018	Weak
Canine	Which Sternotomy Closure Method (Orthopaedic Wire or Suture) Is Recommended in Large Breed Dogs Undergoing a Median Sternotomy?	2018	Weak
Canine	Can Cytosine Arabinoside With Prednisolone Treatment for Canine Meningoencephalitis of Unknown Origin Increase Survival Time Compared to Prednisolone Treatment Alone?	2018	Weak
Canine	In Dogs Bitten by the European Adder (Vipera Berus), Do Corticosteroids and Supportive Treatment Improve Clinical Outcome Compared to Supportive Treatment Alone?	2018	Weak
Canine	In Dogs Does Feeding Raw Dietary Treats Reduce or Prevent Periodontal Disease?	2018	Weak
Canine	Does the Use of Intratesticular Blocks in Dogs Undergoing Orchiectomies Serve as an Effective Adjunctive Analgesic?	2018	Weak
Canine	Is an Anchoring or Pocket Technique Best for Surgical Repair of Cherry Eye in Dogs?	2019	Weak
Canine	Tibial Diaphyseal Fracture Rates Following Tibial Tuberosity Advancement Rapid (TTAR) and Traditional Tibial Tuberosity Advancement (tTTA)	2019	Weak
Canine	Treatment Duration With Steroid Monotherapy in Dogs With Steroid Responsive Meningitis-Arteritis	2019	Weak
Canine	Outcome of Electrosurgery Versus Scalpel Blade for Intestinal Incisions in Dogs	2019	Weak
Canine	In canine cranial cruciate ligament rupture is outcome following TPLO improved compared with lateral suture?	2019	Weak
Canine	There is no superior treatment method for medial shoulder instability in dogs	2020	Weak
Canine	Healing of equine heel bulb lacerations: Evidence behind casting compared to bandaging alone	2020	Weak
Canine	In female dogs undergoing elective neutering is ovariectomy or ovariohysterectomy superior?	2020	Weak
Canine	Comparison of epidural morphine and buprenorphine for hindlimb orthopaedic surgery in dogs	2020	Weak
Canine	It is unclear what impact pheromonotherapy has on stress in dogs in shelter environments	2020	Weak
Canine	In dogs with metaldehyde intoxication, are benzodiazepines more effective than methocarbamol in relaxing muscles and reducing tremors?	2020	Weak
Canine	Developments in surgical fluid therapy rates in veterinary medicine	2020	Weak
Canine	In dogs diagnosed with osteoarthritis, is meloxicam superior to carprofen for reducing patient discomfort?	2020	Weak
Canine	In pregnant bitches, is elective caesarean section more effective than vaginal delivery at improving puppy survival?	2020	Weak
Canine	In Greyhounds with paw pad corns, is surgical excision more effective at resolving lameness than extirpation?	2020	Weak
Canine	Non-Steroidal Anti-inflammatories: Does carprofen or meloxicam have fewer gastrointestinal side effects?	2020	Weak
Canine	The incidence of uterine pathology in ovariectomised bitches	2020	Weak
Canine	Managing atopic dermatitis in dogs: are antihistamines as effective as glucocorticoids?	2020	Weak
Canine	Does the use of topical honey result in a faster rate of second intention wound healing in dogs?	2020	Weak
Canine	In bitches, is ovariectomy/ovariohysterectomy by laparoscopy less painful postoperatively than by midline open laparotomy?	2021	Weak
Canine	Does ranitidine administration improve gastrointestinal hypomotility in dogs?	2021	Weak
Canine	Do dogs with non-surgically managed cranial cruciate ligament disease have better outcomes with rehabilitation?	2021	Weak
Canine	Uncomplicated gallbladder mucoceles – is it better for prognosis to perform cholecystectomy or medically manage?	2021	Weak
Canine	Comparison of alfaxalone versus propofol as anaesthetic induction agents in increasing the rate of survival and vigour of neonates	2021	Weak
Canine	Does turkey tail as an adjuvant therapy improve the quality of life of canine lymphoma patients?	2021	Weak
Canine	Does occurrence of ventricular arrhythmia reduce the survival rate in dogs with gastric dilatation volvulus (GDV)?	2021	Weak
Canine	Can IDEXX Angio Detect™ accurately detect canine Angiostrongylosis?	2021	Weak
Canine	Can dog appeasing pheromone ameliorate stress behaviours associated with anxiety in mature domestic dogs?	2021	Weak
Canine	The use of metronidazole in adult dogs with acute onset, uncomplicated, diarrhoea	2021	Weak
Canine	Current evidence supporting simultaneous prophylactic gastropexy in canine patients undergoing complete splenectomy	2021	Weak
Canine	Mortality rate comparison of enterotomy and resection and anastomosis (enterectomy) in dogs with foreign-body obstructions	2021	Weak
Equine	No Evidence That Therapeutic Systemic Corticosteroid Administration is Associated With Laminitis in Adult Horses Without Underlying Endocrine or Severe Systemic Disease.	2016	Weak
Equine	Evidence Supporting Intralesional Stem Cell Therapy to Improve Equine Flexor Tendon Healing	2017	Weak
Equine	In Horses With Chronic Laminitis, Do Venograms Compared to Plain Radiographs Give Greater Diagnostic or Prognostic Information?	2017	Weak
Equine	In Adult Horses With Septic Peritonitis, Does Peritoneal Lavage Combined With Antibiotic Therapy Compared to Antibiotic Therapy Alone Improve Survival Rates?	2017	Weak
Equine	The Use of Antibiotics in Broodmares With Post-service Endometritis	2018	Weak
Equine	Tenoscopic Debridement or Surgical Repair for Longitudinal Tears of the Equine Deep Digital Flexor Tendon Within the Digital Flexor Tendon Sheath?	2018	Weak
Equine	Do Oral or Minimally Invasive Cheek Tooth Extraction Techniques Reduce the Incidence of Post-operative Complications in the Horse When Compared to Repulsion Methods?	2018	Weak
Equine	The Effects of Biannual Equine Influenza Vaccine on Performance in Adult Horses	2019	Weak
Equine	Comparing Rest Alone to Bandaging and Rest in Horses With Superficial Digital Flexor Tendinopathy	2019	Weak
Equine	Is removal of proximo-plantar osteochondral fragments necessary in young Thoroughbreds?	2019	Weak
Equine	Does intra-articular injection of antimicrobials alongside corticosteroids or other medications reduce the risk of synovial sepsis?	2019	Weak
Equine	There is no evidence that the addition of antimicrobials reduce the risk of sepsis after intra-articular corticosteroids in horses with arthritis	2020	Weak
Equine	Distal tarsal joints osteoarthritis: Evidence behind bisphosphonates and NSAIDs to improve lameness	2020	Weak
Equine	Are bisphosphonates a more effective treatment than intra-articular steroids in horses with distal hock osteoarthritis?	2020	Weak
Equine	In mares with placentitis does the duration of antibiotic treatment affect foal outcome?	2020	Weak
Equine	In horses with osteoarthritis, is mesenchymal stem cell therapy more effective at managing lameness than intra-articular corticosteroids?	2020	Weak
Equine	In horses with trigeminal-mediated headshaking, is neuromodulation with EquiPENS™ more effective than with electroacupuncture?	2021	Weak
Equine	Is inhaled immunotherapy more effective than environmental management when treating equine asthma?	2021	Weak
Equine	For horses undergoing general anaesthesia, are rope recoveries or free recoveries better?	2021	Weak
Equine	Cryotherapy of the distal limbs: an effective treatment for equine laminitis following onset of lameness?	2021	Weak
Feline	Are Adult Cats Fed on Wet Maintenance Diets Less at Risk of Developing Chronic Kidney Disease Compared to Adult Cats Fed on Dry Maintenance Diets?	2017	Weak
Feline	Is Topical or Systemic Antimicrobial Therapy More Effective for the Treatment of Feline Acne With Secondary Bacterial Infection?	2018	Weak
Feline	Does the Use of Intratesticular Blocks in Cats Undergoing Orchiectomies Serve as an Effective Adjunctive Analgesic?	2018	Weak
Feline	Percutaneous Drainage in the Management of Urethral Blockages in Cats	2018	Weak
Feline	Reluxation Rates Following Different Techniques for Open Stabilisation of Feline Coxofemoral Dislocations	2019	Weak
Feline	Can Iodine-restricted Diets Normalise Serum Total Thyroxine (TT4) and Subsequently Improve Clinical Signs in Cats With Hyperthyroidism?	2019	Weak
Feline	Should Levetiracetam or Imepitoin Be Used in Preference as Second-line Treatment in Pharmacoresistent Epileptic Cats?	2019	Weak
Feline	Is a cross-match necessary before a cat’s first blood transfusion?	2020	Weak
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