|Fishing line suture: cost-saving alternative for atraumatic intracutaneous skin closure. Randomized clinical trial in Rwanda
|Freudenberg S, Nyonde M, Mkony C, Bay F, Wilhelm T, Post S
This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn.
Two suture materials were examined:
homemade fishing line suture (using a 23.5-gauge injection needle and 0.25 mm fishing nylon), and
commercial nylon (Ethilon 3-0 with an FS 2 needle).
Type of intervention
Treatment (suture material).
Economic study type
The study population comprised patients of all ages with uninfected surgical or traumatic wounds (Grade I and II) at any site of the body. Only wounds that could be closed by an intracutaneous suture were considered.
The setting was a hospital. The economic study was carried out in Rwanda.
Dates to which data relate
The effectiveness and resource use data were gathered from November 2002 to March 2003. The price year was not reported.
Source of effectiveness data
The effectiveness evidence was derived from a single study.
Link between effectiveness and cost data
The costing was not carried out on the same sample of patients as that used in the clinical study.
Power calculations were carried out. These showed that the sample of patients included in the study had a power of 0.8 and allowed a Type-I error of 0.05. A sample of 220 consecutive wounds in 199 patients was recruited consecutively. However, 20 wounds were not considered because of the death of the patient (n=3), checkout without further consultation (n=10), or a protocol violation (n=8). Thus, the final study sample comprised 200 wounds, 102 in the fishing line group (group A) and 98 in the Ethilon group (group B). Group A patients had a mean age of 30.1 years and 65 were men. Group B patients had a mean age of 29.5 years and 58 were men.
This was a prospective, double-blinded, randomised clinical trial. Details on the centres were the study was carried out were not reported. The unit of randomisation was the wound, and multiple wounds on one patient were randomised separately. Randomisation was based on standard random number tables. The patients were followed until removal of the suture. It would appear that no patient was lost to the follow-up assessment. A surgeon, who was neither involved in the skin closure nor informed about the identity of the suture material, assessed the outcomes.
Analysis of effectiveness
The basis of the analysis of the clinical study was not explicitly stated. The primary outcome measure was the difference in mean wound score. This was defined using the modified Hollander wound score, in which the quality of wound healing was classified as 'not disturbed' (score 0 - 1 = class A), having minor disturbance (score 2 - 4 = class B), or having major disturbance (score >4 = class C). Other outcome measures were time needed for suture, opinions of surgeons about handling the suture, and problems associated with removing the suture. At baseline, the study groups were comparable in terms of demographics, wound characteristics and qualification of the attending surgeon. The association between baseline characteristics and the class of wound healing was investigated.
No statistically significant differences between groups were observed for any of the outcome measures. The time needed for suturing (in seconds per centimetre) was significantly different depending on the qualification of the surgeon (nurse, surgeon in training, or fully trained surgeon), but no significant differences were observed between the groups.
The effectiveness analysis showed that the two interventions were equally effective in terms of the clinical outcomes.
Measure of benefits used in the economic analysis
No summary benefit measure was used in the economic evaluation because, owing to the equivalence of the two interventions, a cost-minimisation analysis was carried out.
Only the cost of the material was included in the economic evaluation. Discounting was not relevant since the costs were incurred during a short timeframe. The unit costs were presented. Resources use was not evaluated since only the cost of one unit was considered. The costs were estimated on the basis of local sources. The cost of the homemade suture included the salary of the local producer on a per-unit basis. The price year was not reported.
Statistical analysis of costs
The costs were treated deterministically.
The indirect costs were not considered.
Sensitivity analyses were not carried out.
Estimated benefits used in the economic analysis
See the 'Effectiveness Results' section.
The cost per unit was $2.30 for the 3-0 Ethilon suture and $0.07 for the homemade fishing nylon.
Synthesis of costs and benefits
A synthesis of the costs and benefits was not relevant as a cost-minimisation analysis was carried out.
Both homemade fishing suture and Ethilon suture were rated as "practical" and "very practical" by all surgeons, and no additional time was required for either suture. No difference in clinical effects was detected. However, the use of fishing nylon would result in substantial cost-savings, and would allow 30 surgical skin closures to be performed for the cost of one commercial thread. Quality assurance offered by the commercial brand was unlikely to justify the 30-fold difference in price between the two suture products.
CRD COMMENTARY - Selection of comparators
The selection of the comparators was appropriate as they reflected two possible suture materials in Rwanda. You should decide whether they are valid comparators in your own setting.
Validity of estimate of measure of effectiveness
The effectiveness evidence came from a clinical trial, which was appropriate for the study question. Power calculations were carried out to ensure the appropriateness of the study sample, and consecutive patients were enrolled. The internal validity of the analysis was enhanced by the use of a blinded design and a comparable group of patients. Further, statistical analyses were carried out to assess the impact of baseline factors on the results of the study.
Validity of estimate of measure of benefit
No summary benefit measure was used in the analysis because a cost-minimisation analysis was conducted. Please refer to the comments in the 'Validity of estimate of measure of effectiveness' field (above).
Validity of estimate of costs
The authors did not state explicitly which perspective was adopted in the study. Only the costs of the suture materials were included in the economic evaluation. The unit costs were provided and the source of the data was reported. However, the costs were treated deterministically and the price year was not reported.
The authors did not compare their findings with those from other studies. They also d not address the issue of the generalisability of the study results to other settings. Sensitivity analyses were not carried out, which limits the external validity of the study.
Implications of the study
The study results supported the use of homemade fishing nylon as a suture material for skin closures.
Source of funding
Supported by the German Academic Exchange Service (DAAD).
Freudenberg S, Nyonde M, Mkony C, Bay F, Wilhelm T, Post S. Fishing line suture: cost-saving alternative for atraumatic intracutaneous skin closure. Randomized clinical trial in Rwanda. World Journal of Surgery 2004; 28(4): 421-424
Other publications of related interest
Freudenberg S, Samel S, Sturm J, et al. The improvised atraumatic suture: a cost-reducing technique, not only for the tropics? Tropical Doctor 2001;31:166-7.
Subject indexing assigned by NLM
Adult; Analysis of Variance; Cost-Benefit Analysis; Dermatologic Surgical Procedures; Female; Humans; Male; Nylons; Private Sector; Rwanda; Skin /injuries; Sutures /economics /standards; Treatment Outcome
Date bibliographic record published
Date abstract record published