What do systematic reviews say?

Live zoster vaccine vs placebo

Live zoster vaccine showed no clear difference in dropoutsClinical or laboratory criteria compared with placebo (moderate certainty).

• Vaccines for preventing herpes zoster in older adults 2023 · Cochrane Headline outcomes only
  RR 0.99 [0.9, 1.08]
  3 studies · 38916 participants
  Moderate

Recombinant zoster vaccine vs placebo

Recombinant zoster vaccine showed no clear difference in participants with adverse events ‐ deathClinical criteria compared with placebo (moderate certainty).

• Vaccines for preventing herpes zoster in older adults 2023 · Cochrane Headline outcomes only
  RR 0.94 [0.84, 1.04]
  2 studies · 29311 participants
  Moderate

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

Condiments/seasonings fortified with iron plus other micronutrients may leads to lower iron deficiency (as defined by the trialists based on a biomarker of… compared with condiments/seasonings fortified with other micronutrients except iron (low certainty).

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  RR 0.36 [0.19, 0.69]
  4 studies · 1154 participants
  Low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  5 studies · 1251 participants
  Very low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 158 participants
  Low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  5 studies · 2808 participants
  Very low

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

Condiments/seasonings fortified with iron showed no clear difference in iron deficiency (as defined by the trialists based on a biomarker of… compared with unfortified condiments/seasonings (moderate certainty).

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  RR 0.33 [0.11, 1.01]
  2 studies · 391 participants
  Moderate

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  6 studies · 4459 participants
  Very low

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 240 participants
  Low

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 240 participants
  Low

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  5 studies · 1270 participants
  Very low

Methylphenidate vs placebo or no intervention

It is very uncertain whether methylphenidate changes proportion of participants with one or more serious adverse events compared with placebo or no intervention (very low certainty).

• Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD) 2023 · Cochrane Headline outcomes only
  RR 0.8 [0.39, 1.67]
  26 studies · 3673 participants
  Very low

Methylphenidate vs placebo or no intervention

It is very uncertain whether methylphenidate changes proportion of participants with one or more adverse events… compared with placebo or no intervention (very low certainty).

• Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD) 2023 · Cochrane Headline outcomes only
  RR 1.23 [1.11, 1.37]
  35 studies · 5342 participants
  Very low

Methylphenidate vs placebo or no intervention

It is very uncertain whether methylphenidate changes general behaviour: all parallel‐group trials and first‐period… compared with placebo or no intervention (very low certainty).

• Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD) 2023 · Cochrane Headline outcomes only
  no estimate extracted
  7 studies · 792 participants
  Very low

Methylphenidate vs placebo or no intervention

It is very uncertain whether methylphenidate changes quality of life (parent‐rated) compared with placebo or no intervention (very low certainty).

• Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD) 2023 · Cochrane Headline outcomes only
  SMD 0.4
  4 studies · 608 participants
  Very low

Perampanel add‐on vs placebo

Perampanel add‐on leads to higher ≥ 50% reduction in seizure frequency compared with placebo (high certainty).

• Perampanel add‐on for drug‐resistant focal epilepsy 2023 · Cochrane Headline outcomes only
  RR 1.67 [1.43, 1.95]
  7 studies · 2524 participants
  High

Perampanel add‐on vs placebo

Perampanel add‐on may leads to higher seizure freedom compared with placebo (low certainty).

• Perampanel add‐on for drug‐resistant focal epilepsy 2023 · Cochrane Headline outcomes only
  RR 2.5 [1.38, 4.54]
  5 studies · 2323 participants
  Low