Table 5 NHMRC FORM framework

Evidence base

C–Satisfactory

One or two level III studies with a low risk of bias, or level I or II studies with a moderate risk of bias

Quantity: Total of 6 studies

Level II: 2 studies;

Level III-2: 1 study;

Level III-3: 2 studies

Level IV: 1 study;

Consistency

C–Satisfactory

Some inconsistency

Multiple study designs

All included studies used 40% urea

Good consistency with diagnostic criteria

Varied outcomes but some consistency

Clinical impact

D–Poor

Slight or restricted

While four studies reported statistical significance, clinical significance was not reported at all.

Generalisability

B–Good

Population(s) studied in body of evidence is/are similar to the target population

Population studied in the evidence base is similar to the target population;

Age range: 22–78 years

Consistent diagnostic criteria and concentration of urea used

Grade of recommendations

C–Satisfactory

Body of evidence provides some support for recommendation(s) but care should be taken in its application

Overall, most studies are of moderate methodological quality;

There was consistency noticed in the diagnostic criteria, intervention/control and outcomes measured.

The lack of long-term follow-up existed.